I spied him immediately, waiting further along the platform at Rennes station, flanked by two fair-haired girls.

“Good trip?” he inquired. “And who’s this little girl you’ve brought with you?”

“Say hello, sweetie,” I prompted, as Tadpole, my daughter, clung to my legs. “This is Mummy’s friend James.”

“And these are my girls, Amanda and Carrie,” said James, addressing his words to Tadpole. The tall, long-limbed girl wearing fine metal-rimmed glasses was Carrie, the older of the two; Amanda was shorter, curvier and looked more approachable. Both had spent their whole lives in Brittany, but to me they looked unmistakably English.

I would have blanched a few weeks earlier if someone had told me I was about to plunge into a serious relationship with a divorced older man, with children of his own and emotional baggage far heavier than the weekend bag which now dangled from his shoulder. And that I would meet him through my blog, petite anglaise. On paper, it seemed like folly. But in practice?

Well, it had often struck me that Tadpole’s father, Mr Frog, and I seemed like children playing at being grown-ups, whereas James seemed like the real thing. As we drove to his home, I listened to how his tone changed when he spoke to Amanda and Carrie, hearing the gentle authority in his voice. I was surprised, but impressed, to see that he disappeared up into the attic that night to read to them before bedtime.

First I had known James as a lover, then as a friend. Now, two months into the relationship, I was discovering another facet of his character, and the more three-dimensional he became, the more attractive I found him. I hoped that seeing me as a mother – as opposed to petite anglaise, or a lover – made him feel the same way.

Back in Paris, little had changed on the surface. Mr Frog had agreed to move out but had yet to find a new flat. We led our separate lives under the same roof just as we always had: we fed ourselves, I wrote my blog, he watched TV or worked on his laptop. I made no protest when he left his dishes in the sink or staggered in late, his breath heavy with alcohol. There seemed little point in seeking confrontation these days, and I was cutting Mr Frog more slack than I ever had before.

“It must be excruciating, having to live together while you wait for him to move,” said James sympathetically when I made another visit to Rennes, this time without Tadpole.

“But it must be really hard for him too. I was in his shoes once, remember? When my wife ended things, I could tell she couldn’t wait to move me out and her new guy in. I think I dug in my heels and stuck around for far longer than I should have done. I didn’t see why I should make things easier for her.”

It was Saturday evening and we were sitting in a tiny Mexican restaurant. I’d noticed when we entered that the owner seemed to know him well, and I couldn’t help wondering who else James had brought here over the years. His ex-wife? Eve, his former girlfriend?

James put his hand to his jacket pocket, saying: “On a happier note, I’ve got a little something for you.”

For a split second I wondered how I would react if James withdrew a jewellery case. But there was no velvet box. Instead he handed me a jangling set of keys. “I wanted you to have these. From now on, my place is yours. If you ever need to come here, if you ever need to get away, you’ll always be welcome.”

I hesitated and then said: “For a moment there, I half wondered whether you were about to pull out an engagement ring . . .”

“I hope you weren’t too disappointed?” he said slowly, taking my hand in his, still clenched around the keys, and bringing it to his lips. “As a matter of fact, I would very much like to marry you one day.

“If you’d have me, that is.” I gasped. It couldn’t be called a proposal, exactly, couched so cautiously in the conditional tense, but for the first time in my life I was with a man who could conceive of marrying me one day, and the idea thrilled me. All those arguments I’d paraded on my blog when I’d spoken of Mr Frog’s reluctance to tie the knot now seemed pitiful and misguided. He’d been right all along: pragmatism was no basis for making such a decision. But I’d quietly assumed that James’s divorce would have rendered wedding vows devoid of all meaning for him. Apparently I’d been wrong.

Until now I had been updating my blog regularly on the emotional rollercoaster of my life. My regular readers had developed a voracious appetite for posts that shocked or thrilled. My life had become entertainment to be sampled by strangers for their vicarious pleasure, safe from harm, hidden behind their monitors.

WHEN Mr Frog finally moved out that summer and the dust began to settle, I updated petite anglaise less often. I was posting maybe 15 times a month – half as much as I used to. A rumble of discontent began to make itself heard in my comments box. Where was their daily fix?

“I have plotted a graph,” wrote Germain. “On one axis the number of petite posts per week. On the other axis a date-line. There is a clearly visible fall in the number of posts right about the time ‘Lover’ came along. I wish he hadn’t.”

Such comments brought home to me forcefully that for some I was just a provider of entertainment, not a person in my own right who deserved a shot at happiness and tranquillity. And yet my life had taken a turn for the calmer, and for me it was a profound relief to feel able to live life more fully offline.

There were, however, a few entries I’d been holding in reserve, out of respect for Mr Frog’s feelings. Now that a couple of months had elapsed, I allowed myself to admit that James and I had met in a Paris hotel room when I was still in a relationship with Mr Frog. There was no sex scene – petite anglaise was far too coy for that – but I knew my confession would shake things up, and I braced myself for the inevitable comments box fallout.

“Do we really need to know this?” Teresa was quick to complain. “This is personal stuff you are divulging, stuff that I would cringe for anyone to know if it were me . . . Once you send something out into cyber-space, you can’t reel it back in.”

“Why do I write posts like this?” petite anglaise pondered in reply. “I’m not sure I even know myself. To commit certain things to memory. To flex my tiny writing muscles. To romanticise my life. As letters to someone in particular. As therapy. To exorcise guilt. I’m not sure it matters why, as long as no damage is done.”

When the holidays were over, I was trapped in Paris with Tadpole once more, feeling sorry for myself. Meanwhile, in Brittany, James and his kids were spending time cheering up his former girlfriend, Eve, who was feeling lonely while her new boyfriend was away.

It was into Eve’s arms that James had fallen when his marriage fell apart; she who had healed his pain and made him whole again. I made the mistake of looking over the early e-mails James had sent to petite anglaise, explaining this. The drama of their shared history, the intensity of emotions he’d described unsettled me now. Could our story ever rival theirs? As I read, I hated myself for wishing I could overwrite whole sections of his past with my blog, destroying his baggage with a controlled explosion.

After snapping at James in a fit of fury on the phone because he and the girls were staying overnight at Eve’s house, I tried to exorcise my jealousy the only way I knew how: by writing about it. I wanted petite anglaise to make my apology: she had a knack of expressing complex feelings so much more vividly than I ever could on the phone.

If there was one thing James professed to love about my alter ego and me, it was our disarming honesty. But, although I bared my soul up to a point, I kept my ugliest, darkest thoughts off the page.

There was something else. James brought out my British side. Instead of croissants, I now ate granary toast and marmalade for breakfast, washed down with a bottomless cup of tea, in place of my bowl of café au lait. We spoke only English when we were together, whereas with Mr Frog at least half our conversations had been in French. At James’s place in Rennes we watched British tele-vision, or leafed through British magazines; we drank at an Irish bar on the Place du Parlement de Bretagne in the evenings. At weekends James even played the occasional game of cricket with a local expat team.

When we’d first met, I’d found this “Britishness” appealing. The shared cultural references, the books and TV shows we had in common, all these things were shortcuts, allowing us to get to know each other more quickly, giving us an easy familiarity from the outset, over and above the head start which petite anglaise had given us. But now, a few months down the line, the novelty was beginning to wear off. I’d caught myself cringing a couple of times when I overheard James speaking his rather stilted French in shops.

In the long term, did I really want to live a British life in France? By throwing in my lot with James, my inner voice whispered, wouldn’t I be turning my back on the French way of life that had drawn me to France in the first place?

And another thing: my relationship with Mr Frog was improving now that we no longer lived together. He bought a new suit – a change from James’s T-shirts and jeans – and I had to admit to myself that he looked quite handsome.

I was adept at justifying everything I’d done – to my readers, to my friends, even to myself – reasoning that because Mr Frog now spent far more one-to-one time with his daughter, and they were closer than ever before, everyone was better off. But that meant glossing over the fact that I’d robbed Tadpole of the chance to be with us both at the same time. Seeing how pathetically pleased she looked on the rare occasions when we did get together made my heart heavy.

James’s unwavering certitude was the best antidote to my doubts that autumn. My faith in us was renewed. The plan was that after next summer Tadpole and I would go to live with him in Brittany. I wanted to give her the picture-postcard school and cottage I dreamt of with a rambling garden.

The first time I’d visited James, his apartment had been spotless; on subsequent visits, less so. It wasn’t dirty – just cluttered and riotously untidy – but if Tadpole and I were to move in, I was adamant that James would have to change his ways, if only to make space for us.

Whenever I visited I had to hold myself in check, even though I was itching to sort the paperwork fanned across the floor around James’s desk, or to gather up the clothes strewn across every surface of his bedroom. That was how he liked things, James insisted and, until I moved in for good, that was how things would stay.

Then came Christmas. “I don’t want my life to be perpetually mapped out like some sort of military campaign,” objected James, an uncharacteristic hint of irritation creeping into his voice when I prodded him, for the sixth time, about his daughters’ Christmas whereabouts.

“I’m sorry. I know I keep hassling you,” I said, cradling the phone as I squeezed my teabag with the back of a teaspoon. “But playing at happy families isn’t easy. We have to take so many different people into account: your ex, my ex, all our children’s grandparents . . .”

In the event, I boarded the train to Rennes two days before Christmas, trembling with anticipation. Amanda and Carrie were with their mother, and Tadpole was with her grandparents, so James and I would spend Christmas alone, as I’d hoped.

I pictured us eating a candle-lit meal for two, retiring early with a bottle of champagne. But when my nose started to drip like a leaking tap and my sinuses began to ache, I knew I was in trouble. By the time the train pulled into Rennes station, I was feverish and dizzy. I’d desperately wanted our first Christmas together to be magical, to mean something; but it passed in a feverish blur.

“Hey, it’s a pity, I know, but there’s no point getting all worked up about it, love,” James said reasonably, putting his palm to my clammy forehead. I resisted the urge to swat his hand away. I didn’t want reasonable. I wanted romance and passion; our old intensity. I wanted, at the very least, to see some evidence that my bitter disappointment was matched by his.

Where had he gone, the James who sent me all those knee-weakening, eloquent e-mails back in April? The man who once confessed he was so captivated by the movement of my hips every time I walked across the room that he constantly had to suppress the urge to pick me up and carry me to the nearest bed?

“Just think, next Christmas you’ll be living here with me, and we’ll laugh about this,” said James, smoothing back my hair with a paternal gesture which I’d seen him use before, with Amanda and Carrie. “Now, you stay there, and I’ll go and make you some more hot lemon.”

I’d asked for passion, and Father Christmas had brought me Lemsip. THE end came when I least expected it – on James’s first visit to Paris after Christmas. Along with half my office, I had been invited to a colleague’s hen night. Tadpole was with her daddy, and James would be staying home alone. I’d been tempted to bale out, but James would not hear of it. He didn’t mind me abandoning him in the slightest – or so he’d said – insisting he had plenty of work to be getting on with.

As the metro screeched into Buttes Chaumont station, I plotted. I’ll jump into the shower, I thought, then drag him to bed for a while, until it’s time to get my glad rags on. Before I go, I’ll order him a pizza. Save him cooking for one.

“Hi, honey, I’m home,” I called as I stepped inside, aiming for some approximation of an American accent but failing miserably. There was no reply. Usually, at the merest hint of the lift door opening, or of my footfalls on the landing, James would rush to the door.

I found him sitting motionless on the sofa, a crime novel hanging limply from his hand. He was chalky pale. Either he’d had some bad news – his father perhaps? – or he was coming down with something nasty. So much for diving between the sheets for a while, I thought, crestfallen.

“You okay? You look pretty rough . . .” I made no move to join him on the sofa: there was something about his posture that didn’t invite contact. Instead I hovered uncertainly in the middle of the room.

“Something I ate, I think.” He put a hand to his stomach. “I’m not feeling too good.”

James was clean-shaven, and wore a biscuit-coloured jumper, both of which exaggerated his pallor. I definitely preferred him with a five o’clock shadow. He’d put on weight since we first met. We both had: contentment was taking its toll. My trousers fitted more snugly around my hips than before, but in James the gain was most visible in his face: no longer taut and angular, the skin around his jawline was slackening.

“Catherine?”

Something in his voice, in the way he said my name, derailed me, and I straightened up with a sharp intake of breath, waiting mutely for what in a blinding flash of sixth sense I suddenly knew must follow. He closed his eyes for a second and swallowed with a grimace, as though clearing his throat of bile.

“I’m sorry,” he said finally, “but I just can’t do this any more.”

There was a ringing in my ears and for a few seconds I thought I would faint, sidestep-ping my body to avoid hearing whatever he was about to add. But my vision cleared: there was to be no escape.

“I wish I didn’t feel this way,” he continued in a pained voice,

“I wanted so much to make this work.”

“I don’t believe I’m hearing this, after everything we . . . after everything I . . .” But there seemed no earthly point in finishing my stunned protest.

“I can’t let things go any further. I can’t let you uproot everything and come to live in Rennes. Because I don’t think I want to spend the rest of my life with you. Not any more.”

I could not raise my head. I had no desire to see the face that went with that voice.

“You don’t love me any more,” I said flatly. Silent tears began to drip onto the inside of my glasses, down the sleeves of my coat.

“I did. I still do. But not enough. I’m so sorry.”

It was over. My world was imploding before my horrified eyes. When I left Mr Frog I’d foolishly, recklessly pinned everything on James, projecting every second of my future onto him. I was aware of the risks, I knew love came with no guarantees, but I’d hurled myself headlong into this new adventure all the same. I’d wanted so desperately to feel things intensely, and my wish had been granted, at a terrible price.

“I want you to leave,” I said suddenly, my words clipped and precise. I would not debase myself by begging him to stay. I listened as he gathered his belongings with merciful speed, his suitcase already packed, the manoeuvre anticipated. I heard him zip his computer pouch closed, ease his arms into the sleeves of his jacket, tie his shoe-laces. The front door closed behind him with a dull thud.

Crumpling on the bed, still wearing my coat, I sobbed noisily, messily, into my pillow until my head throbbed, howling until my throat grew hoarse. But by midnight, dry-eyed, terrifyingly calm, I knew what I had to do. Our relationship had been born out of the blog, so wasn’t it fitting to announce the ending there, for the whole world to see?

This is what I wrote: “I am a rudderless boat turning in dizzy, uncomprehending circles on a sea of noisy tears. He doesn’t want me any more.”

Then I disabled comments. I had no desire to hear a chorus of “I told you so” and “poor you” echoing back at me. A FULL calendar year has now gone by since I first laid eyes on James. I remember the woman I was before petite anglaise came along, that sleepwalker, deeply dissatisfied with her life, seething with resentment but unable to articulate what was wrong.

I remember how by writing about the city around me, about the people in my life, I began to see everything more clearly. I realised that being a mother, being in a relationship, shouldn’t have to mean burying my own needs deep inside, denying their very existence. That way only bitterness lay.

When James fell in love with petite anglaise and came into our lives, I willingly clambered onto a rollercoaster. There were moments when I doubted the wisdom of my actions. Moments when I worried that the blog was living my life for me, or pushing me to reveal more than I should to satisfy my thirst – and my readers’ thirst – for drama, for material, so that the show might go on.

Petite anglaise looked on with interested detachment, using me as a guinea pig, a lab rat, placing me in ever more unexpected situations to see how I would react. All the while furiously scribbling, documenting my emotions, recording my every move.

Maybe it wasn’t really JamesI fell in love with, I think to myself with a sudden blinding flash of clarity. Would it not be fair to say that I fell for my own words, or the image of myself that he reflected back at me, the carefully constructed, larger than life version of me: petite anglaise? Everything she wrote was in some way calculated to charm and seduce, and hadn’t James been the most tangible proof of her success?

Rising from the ashes of two failed relationships, I’m a single mother now, and a woman who is well on the way to owning her first home.

I’ve formed one half of an ill-matched couple for most of my adult life but now, alone, I feel whole, at peace with myself. The desire for flight has finally left me. Given the chance, I wouldn’t trade places with the old me. Nor do I wish that petite anglaise had never existed. She brought me here. And I really like where I’ve wound up.

© Catherine Sanderson 2008

Extracted from Petite Anglaise by Catherine Sanderson, to be published by Penguin on Thursday at £12.99. Copies can be ordered for £11.69, including postage, from The Sunday Times BooksFirst on 0870 165 8585

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