My final journey starts one night. We have all been out somewhere, God knows where, and a group of us ends up back at someone’s flat. This someone is sleeping with David, who will turn out to be my guide to the final frontier.

David and I trade numbers and end up having lunch. He has a powerboat (customised), is familiar with hotels in Monaco and is still, technically, married to somebody else. He never, ever runs out of cocaine.

Our usual evening’s ritual consists of vodka/juice, cocaine, red wine and back again, with cocaine throughout. Twenty-four hours, thirty-six hours, watching the sky go dark behind the blinds, watching it lighten up again, watching it go dark again. Talking, talking, sex, talking and more sex, more lines and another bottle of wine. One night we get back late and the corkscrew has gone missing. We open the bottle with a power drill, sending red splatters all over the kitchen wall. Another evening, David is keen to watch a documentary about Jeffrey Archer, which puts forward the hypothesis that Archer is, medically speaking, a psychopath. Ologists are wheeled on, and someone boils the definition down to 17 features that indicate that this is more likely than not. David applies them to himself and counts 15.

Sex, drugs and anger David decides we will take a holiday to California. I dare to question his choice of dates, and he later apologises for his snarled response.

We arrive at the hotel, and our host is dispatched to get supplies. He turns up much later with a couple of grams and some porn movies. Time passes, and it is decided to phone a couple of girls. When they arrive at our beachfront hotel room, they are a sorry pair. One of them keeps banging on about her ADHD diagnosis. We lie around on the bed and chat, and then David and I invite them into the bath with us. I have just got my dressing gown off and slipped into the bath, when the two of them start having some kind of standoff – doubtless staged – then leave rapidly. I am cross and disappointed, as I have not been with a woman in several years and am feeling extremely up for it.

It is getting light outside. Two more girls are ordered, the bill racks up and up to nearly $2,000, and the cocaine is now liquefying in sticky lumps. David is cross as the new girls are duds, and we try again. The lady on the phone tells us that the only one she has free at this time of the morning is really not that pretty, and in fact, she explains, is black, and do we mind? The girl arrives later on, announcing breezily in the morning sun, “I don’t do girls.”

For Christmas, David decides we should go to Thailand. A week or so before leaving, I go to his flat to collect him before going to dinner with some friends nearby. I find him passed out in his bed. I pick up his camera and idly flick through the images. It’s odd how quickly you learn when you’re in a total rage. I remember a friend managing to do the Rubik’s Cube in minutes while being bollocked for copping off with someone at a teenage party. And there they all are. David finally gets out of bed, and a row ensues, during which he tells me that he got the girl for his godson’s 18th birthday and that he didn’t do anything with her, after which he smashes his phone against the wall.

Valentine’s Day comes. He does not bring me anything, apart from the usual cocaine. Later on, probably about 7am, he says, “I don’t want to be patronising, but I don’t want to marry you.”

One day in March, I have a premonition that I have still not hit rock bottom. Despite years spent contemplating suicide, I have somehow stayed afloat. Even before that time, I have been telling people that the water is “just up to my nose”.

I cry all day I walk round and round the flat. I see a piece of paper on the floor, with train times to a town in the north. Through the haze of chemicals, I begin to feel something. I make my way back to the living room and begin to go through all the receipts that are spread out on the table. And, within seconds, as you do, I find what I am looking for – a credit card receipt for a strip club, dated the Saturday when I thought he was away seeing a dying relative. Something makes me get down on the ground, and there is part of a condom wrapper. We have hardly used them in our entire relationship, and certainly not recently. I pick up a pot plant and hurl it against the wall. It leaves a dent in the plaster and a spray of earth that clings to the white paint in a huge fan.

The feeling of betrayal goes far deeper. It feels like my whole life being repeated. I call him and leave a message, during which I say things I will not be able to take back, drink another can of beer and walk out of the flat, ripping a book I have given him to shreds on the way out.

Days later, we meet in a pub, where he subjects me to a torture session during which I, to my everlasting disgust and shame, actually beg to go back with him.

I cry all day, most days. Two days before my birthday, I wake up, and just after that quarter-second of delicious peace, before I remember why I have to cry, I hear a loud bang in the bathroom. I lie there, thinking someone has thrown a stone at my window. But I am high up on the third floor. I get up and go to see what is happening. The mirror, the old mirror that was there when I moved in, has spontaneously cracked all the way across.

On my birthday, I wake up knowing that I want to die. I drink all day in my flat, crying and crying. David does not call. At midnight I get out my collection of Valium and temazepam and begin to swallow them. I text David, informing him of what I have done, and the phone begins beeping with texts and rings. I drink more vodka and lie back.

I wake up the following evening. I am woken by the phone. It’s a friend inviting me over for supper. I ask her why she is calling me so early in the morning. Amazingly, I actually get up, have some more vodka and get on the Tube. I am having trouble walking. Later, ranting incoherently, I have to be put to bed in her spare room.

A couple of days later, I get some heroin, drink more vodka and try to cut my wrists in the bath, but I just cannot get it right. There is no sign of David.

I plan yet again. I will get it right this time. I spend another day semi-passed-out on the wooden floor next to the ashtray.

Another day spent drinking and crying. Another hour, another unsent text. Marlboro Lights. Vodka with a bit of mango juice to take the edge off. Charred tinfoil. My thumb stinging from the lighter wheel. A hot bath. My ears ringing, my eyes starting to roll. Goodbye, everybody.

Four hours later. A cold bath. My neck hurts from where I’ve passed out with my head on the side. It’s light outside. Shit. Hello, world!

The journey begins The assessor at a clinic looks at me with concern. Since my first overdose, I’ve got into the habit of slumping when I sit down anywhere. I clutch onto banisters and shuffle slightly when I walk. He asks me if I have gone for any checkups after my attempts to end it all. A week or so later, I get a letter saying they will not treat me while I am still drinking, and that I should come back in six months when I am sober.

The prospect of getting help finally persuades me that I should give up drinking. I manage to get myself referred to an NHS alcohol clinic. The counsellor seems to speak very slowly.

When you’ve been used to coke-fuelled rapid-fire ravings right in your face all night, normal speech comes out like molasses. He gets me to fill out a drinking diary. I am regularly topping 100 units per week, and he is horrified, as is the nurse who examines me. I try to explain that 60 units is just the baseline – a bottle of wine a night, in other words – but that’s just home drinking. Parties and socialising are extra. Most of the women I know are no different, and some would be much worse.

And so begins a journey. Living from day to day may be a cliché, but it applies here. Somehow I still keep up a face to my friends, even managing to go out at times. Nobody knows about the heroin overdose – I am like the schoolgirl who has secretly given birth in the gym toilets. Over the next two months, I gradually cut down my alcohol intake. I feel like a scientist, a pioneer, with my careful observation of my intake, my little rules, my numbers of glasses.

Then there is the issue of money. I have none. In the middle of this fugged madness, I try, unbelievably, to get yet another agent interested in yet another book idea. And, unbelievably, I try to get an editor interested in yet another feature idea, all to no avail. I go to see a friend who’s worked as a dominatrix to see if I could do that. I turn up at her lovely house, babbling, my left wrist covered in a plaster to hide the crusting cuts.

Next week: What life after alcohol is really like © Tania Glyde 2008. Extracted from Cleaning Up: How I Gave up Drinking and Lived, to be published by Serpent’s Tail on January 10 at £10.99. To buy it for £9.89, including p&p in the UK, call The Sunday Times BooksFirst on 0870 165 8585, or visit timesonline.co.uk/booksfirst

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