In 2000, Britta Phillips walked into our rented rehearsal room wearing corduroy jeans, her hair cut in a bob. She was feminine and gorgeous in a Scandinavian way, with high cheekbones and big green eyes. Her bass was a fiesta-red Fender Precision, a classic 1970s reissue.

My band, Luna, had just lost our major-label deal with Elektra, been dropped by our publisher and let go by our accountant. As if this wasn’t enough, our bass player had quit rock’n’roll for good and flown home to New Zealand.

After all the auditions, my bandmates and I stood on Avenue A and held an impromptu meeting. Our drummer, Lee, was sure that we should hire Britta. I was leaning that way too. The guitarist, Sean, was on the fence: “I don’t know.” That was as close to a unanimous decision as we were going to get.

“Listen,” I said. “No hanky-panky. If anyone gets involved with her, they’re out of the band.” I think I was joking. Perhaps I was half joking.

Britta’s first real show with the band was in Boston. She was perfect, and the Luna fans seemed to think so too. The Washington Post mentioned the “beguiling Britta Phillips” on bass. I liked that they called her beguiling. It made me feel proud.

We flew to Seattle, where we stayed at the Travelodge by the Space Needle. I was feeling a little lonely and fragile, and I missed my son, Jack, who was now eight months old and lived back in New York with Claudia, my wife of seven years. I had met Claudia while performing in a high-school play in 1980, and we both ended up going to Harvard.

At the Fillmore, in San Francisco, we broke out Bonnie and Clyde, a long, sexy French song about a doomed couple, with Britta singing the Brigitte Bardot to my Serge Gainsbourg. It sounded great. I was careful not to look at Britta on stage. My old friend Howard Thompson, the former head of A&R at Elektra, was at the show, and he quietly told me that Britta had “the best visible panty line in rock”. I felt proud again.

Later that year, after a show at the University of Massachusetts, the band was invited to a dorm-room party by a pretty blonde student who had been dancing wildly in front of me throughout our set. “You can tell how someone is in bed,” Lee said, “from how they dance.”

She was pretty, but I wasn’t interested. I had stopped noticing the girls in the audience at Luna shows, consumed by my crush on the beautiful girl on stage directly to my right, a crush that wouldn’t go away. I knew I should try to control it. But I couldn’t. I was intoxicated.

I became more intoxicated at the party, after drinking a couple of glasses of student-made punch. It was all so predictable. After half an hour at the party, we drove the van over to the hotel. I deliberately left my pack of cigarettes in the van that night, which gave me an excuse to knock on Britta’s door.

She gave me a cigarette and a kiss. I shouldn’t have done that. It led to a world of hurt. By the next day, we were co-conspirators. We rode home in the van to New York that Sunday afternoon with a secret. The morning started off well. I was in a semi-pleasant daze from the night before. But, as the van rattled down FDR Drive, I started to panic. I was shaking as I approached the door of my building on Bleecker Street, wondering how I could possibly walk into my apartment and not have the whole thing written all over my face. I opened the door, was greeted by my wife and son and dog, and life went on. Yet something had changed.

We are all capable of grand deceptions. Or at least I am. It’s difficult at first, terrifying even, but you get used to it. Sort of.

Britta and I carried on an affair for months. In Pittsburgh or Nashville – or anywhere – we would rush to our hotel rooms to meet in secret. It was exhilarating. It was also awful. I was lying to everyone around me – to my wife, friends, family and booking agent. Interviewers asked: “Has the dynamic changed with a woman in the band?” Umm, yes.

Sean and Lee called a meeting, ostensibly to discuss the making of our next record. Britta wasn’t invited. They were aware that something was going on between Britta and me. They were concerned. “You’re right,” I said. “It’s dangerous. It has to end.”

The affair continued. Claudia and I had been in denial about the state of our marriage – we loved each other, somewhere, but we had lost the romantic connection. Our life together was about diapers and chores and being sure not to wake the baby. Still, I had no intention of leaving Claudia and Jack – the very thought of it struck fear in my heart. Yet I couldn’t stop.

It was hard to travel around the country with the lovely Britta Phillips – getting on stage and singing together and drinking champagne after the shows – then think that I was going to just say no. I had real feelings for Britta, feelings that were beyond my control. I promised myself I would make a move, a decision, do something to fix my life. Soon, I said, soon I will fix things.

The decision was made for me by the maid at the Days Inn, in Fredonia, New York. We were recording what would turn out to be our last album. I booked a hotel room a 10-minute drive away; Britta came with me. On the final day of mixing, I checked out of the hotel. When I arrived at the studio, there was a phone call waiting for me. It was Claudia, who had just called the hotel. The receptionist had put her call through to my room, where it was answered by the maid. “Oh, no,” she said. “They just left.” With that utterance, I was cooked.

Claudia ordered me to get my ass on a plane home – immediately. I felt sick to my stomach. I took that JetBlue plane from Buffalo to JFK a bundle of nerves, feeling like I was about to walk the plank. Walk the plank I did, through my apartment door into a sea of anger and tears – and questions, questions, questions. Claudia made it easier than it might have been. She gave me two choices and five days to decide: either Britta would leave Luna, or I would pack my things and move out. I was panic-stricken. I honestly didn’t know what to do.

How do we make the important decisions in our lives? I was at a crossroads. I had no idea what I would do come Friday. I didn’t want to leave Claudia and Jack. But neither did I want to kick Britta out of Luna and out of my life. Friday rolled around, and I still hadn’t fired Britta. Which meant that I was leaving.

I pulled my suitcase down from the closet shelf, stuffed it with summer clothes, grabbed my 1958 Les Paul and walked out the door. My feet took over. They walked me to the street and out of my marriage. I cabbed it down to my horrid studio at 373 Broadway, where I lay on the floor and cried.

I went out for a tuna melt and a chocolate shake at a greasy diner. It was a gorgeous summer day. I managed a few bites of my sandwich, then walked up Broadway all the way to 14th Street. I had no destination, but at four in the afternoon, I found myself wandering aimlessly down Second Avenue, arriving at the basketball courts at Houston Street. I had unconsciously wandered close to home, if I was still allowed to use that word. At that moment, I looked across Second Avenue and saw our baby-sitter, Nicoleen, pushing Jack along in his stroller, heading home.

I froze. I wanted so badly to run across the street to Jack. He was only a couple weeks shy of his second birthday, and was talking now. I wanted to say hello, but I couldn’t. He was on his way home, and how could I explain to him that, as of noon that day, we no longer shared a roof? I stood there watching my son being wheeled away, feeling as if he no longer belonged to me, as if he was being wheeled out of my life, unable to do anything about it.

This was the worst moment of my life. Of course, I know that other people live through much worse. Mine were the problems of a spoilt and self-indulgent singer-songwriter. Still, this was my moment, and it hurt.

The band went on a tour of Brazil and Argentina. I called home to speak to Jack every day. “Why are you calling here?” Claudia would ask. There was no correct answer. I had always called home. I had stopped wearing my wedding ring and stowed it in the zippered side compartment of my toiletry bag. I could have moved it, but where would I move it to?

In January 2003, Claudia and I signed our divorce papers. This was not a happy day. Quite possibly, we worked harder on our divorce than we had on the marriage. We attended weekly sessions with a mediator to sort out all the issues that divorce entailed – a weekly schedule for Jack, a summer schedule, who would pay for what, what would happen on holidays, what would happen to our joint assets.

After a year and a half of therapy, mediation, anger and sadness, I woke up one morning and didn’t feel like a failure as a husband and a father – I wasn’t miserable any more. Britta and I moved in together, into a cute fourth-floor walk-up in the East Village.

One day, the four of us – Claudia and Jack and Britta and I – went to lunch together. This was Claudia’s idea, and it was a good one. We realised we could all get along and everyone was going to be all right.

Three years later, Britta and I were in the studio, working on a new album for a new label. One Monday during the recording, we called our producer, Tony Visconti, to tell him we’d be late.

“We’re going to City Hall to get married,” I said.

© Dean Wareham 2008

Extracted from Black Postcards: A Rock & Roll Romance, published by Penguin Press. Buy it at the Sunday Times BooksFirst price of £14.99 (including p&p). Call 0870 165 8585

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