EVERY SO often an ex-patient drops in for a "top-up". They join us in Process Group and then we fill the seats and floor of the sitting room to hear about their life, their time here, and what things are like for them out there now.

For them, I like to think that this brief experience is a terrible reminder of what it would be like if they were to go wrong again. Returning here, for months perhaps, rather than driving off to freedom after their talk.

For me, I struggle to reconcile the horror stories they tell about their past with the calm, recovering addict sitting before me. I also feel like a wounded soldier hearing about life at the front.

Frankie drew up in a Mercedes. He was sharply dressed, with an army haircut, and had the air of someone who was used to commanding men. He was also a Muscular Christian. So Muscular, in fact, that it was less of a surprise when he told us that he had once shot up the heathen in Lebanon on behalf of the Christian Falange. His addiction to gambling started off as another rather un-Christian hobby.

"I began small: horseracing, football, cards - that sort of thing," he says. "Soon I was betting on flies going up the wall, or the village of the next guy we shot."

Frankie spent all his salary gambling. His wife and kids left him and still he went on. He could never win enough or lose too much.

"I started stealing money. First of all from friends, then from army funds. I stole from a fund that looked after families of dead comrades."

Then things got worse.

"There's a lot of money to be made from drugs where I come from, and I wanted to profit. I don't take drugs. I don't even like drugs. Actually I used to beat up f---ing drug addicts."

Finally, Frankie was convicted of fraud but because of his army rank he got a lighter sentence than he would otherwise have done. When he came out, however, his life was ruined and he was still gambling.

"I discovered an AA branch in Beirut. There's one place there, I think, and, believe me, it's really anonymous. A guy there told me about this place."

Frankie is now studying at teacher training college.

When he'd gone, all my instincts told me Frankie was a bad person. Sometimes I have to remember that every kind of human being winds up in recovery.

But just as we're told here that recovery won't turn you from Claude Monet into Rolf Harris, or from F Scott Fitzgerald into Jackie Collins, so too, I thought, it won't turn you from a bad human being into a good one. If, indeed, Frankie is bad.