I was a middle-class heroin addict

When Lucy saw the photographs of 21-year-old Rachel Whitear curled up with the syringe in her hand, she saw herself. "Seeing the pictures of that needle, it was such a familiar sight to me. I've got really bad scars round the tops of my legs from injecting.

I nearly lost my fingers once, from blood poisoning. And when someone dies alone like that, I know what happens. They may have been with someone, but the other person will be so terrified they'll run. I knew someone who wasn't found for eight weeks."

Whitear's body, as seen in the shocking photographs released 10 days ago by her parents, lay undiscovered on a bedsit floor for three days. Once a happy schoolgirl, with a loving, middle-class family background, the pretty Hereford girl had 10 GCSEs, A-levels in pyschology and communication studies and a place at Bath University. But tragically it was to be only a short ride from her first fix of heroin to her seedy and lonely death two years later.

Lucy is a very attractive girl, also in her early twenties, slim, stylishly dressed, well-spoken, just the kind of girl you'd like as a friend, or a daughter. She is still astonished that somebody like her, well brought-up, privately educated, from an affluent, loving home in London, became someone who slept in abandoned cars, who pawned precious presents and family jewellery to buy heroin, who was spat at in the street and beaten up by dealers.

But she did and another part of her knows that, although she escaped and has been clean for 18 months, neither she nor her family will ever be quite the same again. She's happy to talk about it if her story will stop even one person doing what she did or give any addicted person the hope that they can recover. She knows, through painful experience, that heroin addiction can happen to anyone.

When Lucy was 18 she was set up for a happy life. She'd done her A-levels at boarding school and she wanted to work in design. Her exam results weren't quite good enough for the university course she'd chosen so she decided to come to London and do retakes while her mother and father, who works for a multinational company, had a period abroad. They found her lodgings in the home of family friends but Lucy soon found herself lonelier than she'd expected. Her immediate friends had all gone off to university or off on gap years and there was nobody in the house her own age.

"I met this guy, I used to pass him every day. He was begging next to a cash point and I found him attractive. We started chatting and became friends. He wasn't sleeping rough, he was staying in someone else's flat and one day he invited me back. I had no idea he was on drugs until I found him using in the next room. I was completely shocked and left."

This wasn't Lucy's first encounter with drugs. When she was 16 she'd had an Etonian boyfriend, part of a group that were quite pro-drugs and had no qualms about experimenting. She'd smoked dope, taken ecstasy, but drew a line between recreational and hard drugs, a line she now thinks is artificial.

"Now I honestly believe even recreational drugs can be dangerous. I tried to avoid this boy, but I was lonely. I'd made a new friend, so I went back to see him. I saw the effect heroin had on him and his mate. It made their problems disappear, drift away. It just appealed to me, so I tried it. I gave him £20 to buy me some and I smoked it. I did enjoy the feeling. It blocked things out, the loneliness went, nothing mattered." The feeling lasts several hours, and then you sleep all night. "I thought I'd only do it a couple of times. I was terrified of my parents finding out, I felt I'd let them down and they'd be horrified, so I got even more upset with myself."

By the end of a week Lucy realised she was addicted. Over the summer her friends noticed something wrong, and Lucy was terrified of them telling her parents. They were back home, but she was out so much she hid her state from them, and by the time they sensed something was wrong and began to quiz her she'd gone off to university.

Lucy began her degree course with a heroin habit. All the new life of university - making friends, seminars, parties - was postponed in favour of the consuming business of feeding an addiction on the generous allowance she received from her trusting parents. Feeling, once again, lonely, she telephoned her boyfriend to come and join her and by the beginning of her second term she'd dropped out and was begging on the streets with him.

"I didn't tell my parents I'd dropped out. We'd made friends with other beggars and were living rough and I turned to begging. So many girls I knew turned to prostitution, but I never did. I've been to a dealer and begged him to let me pay him later, and he'd say, only if you give me a blow job, but I never did. I felt depressed, angry, I didn't know where to turn. Then one day I injected into an artery and my whole hand turned black. At the hospital they said I might lose my fingers, and that's when I called my parents. Three or four weeks on the street was enough."

For the first time Lucy told her parents the truth, and they rescued her and took her to a private clinic to detox, but that is never the end of the story. The real pain of addiction starts when the detox is over. The self-loathing and shame kick in when the drugs which anaesthetised them have gone.

"The initial detox takes 10 to 14 days, but once you're well enough you go to all kinds of therapy. I despised myself and I got very depressed at what I'd done to my family. I cut and starved myself. My mother was coming every day but she didn't understand. For the past year and a bit the people I'd been spending my time with were addicts. When you get clean you're alone again. I missed my boyfriend and the others. You feel they're the only ones who understand, so I met up with them again and relapsed. "

But her parents weren't fooled twice. They knew the signs and whacked her back in hospital, even though Lucy was to relapse again before her parents tried the tactic of tough love. "When they found out the third time my dad felt I'd taken them for granted. He found me a room and left me to it. I got beaten up really badly by some dealers, and after that my mum said I could come home but not if I was using. For me tough love was my dad saying: 'I still love you but we can't have you treating us badly', and my mum saying 'no' to me. At that point I went to the doctor and started on methadone."

That was 18 months ago. It is still a lonely and difficult journey. Lucy cut all her contacts, erased the dealers' numbers from her phone, went three and four times a week to drug counsellors and groups. She made herself be with people who'd gone clean and stayed that way for a number of years. At Christmas she sent cards to all her old, pre-addiction friends. She told her old boyfriend never to contact her again and she stopped herself looking for another until she's sorted herself out. She got a job in an advertising office and one evening she found herself answering her mother's phone.

"My mother got involved with FA, Families Anonymous, for the families of users and she became a helpline volunteer. One night I answered her phone and it was a distraught woman who'd just found out her son was using. That night I spent two-and-a-half hours on the phone to three diffeent parents, telling them about their child's perspective and they said it really helped. You're so selfish when you're using, you don't think of anyone else."

Talking to Lucy I could see that being clean doesn't mean being free. She always has a guilt of what she did to her family. "It took a long time to rebuild the trust.

"They never stopped loving me, but my mum was scared of having me in the house and she was on anti-depressants because she blamed herself. There are long-term repercussions. It's hard when I go for a job because there are big gaps in my CV. I have drug-related epilepsy. And obviously I didn't finish my degree course, so I'm not qualified for anything. Although I had ambitions to be a successful designer, I can only do low-grade office jobs."

Lucy's life now is very controlled. She doesn't allow herself to get drunk or have even a puff of weed. "I'm not saying everyone who uses recreational drugs will go on to be an addict, but some will. I would advise everyone not to go down that road. It's not a nice place to be and it's a long, long ladder to climb back up." And some never make it.