For three years my life always seemed to be half a step forward, two steps back, sometimes with a shove.

Then came the bit where, at last, there seemed to be light at the end of the tunnel.

Troubled son Matt, now 19, decided that it might be best all round if he didn't live with me.

Rejecting offers of help from an elder half-sister the other side of London, he actually found digs himself. Matt saw this as a grand achievement, and in some ways it was as he usually drifts without any idea or willingness to sort out life's little problems.

My role was to put down the two weeks' deposit and then help out with the extortionate rent on his dingy room for the first month or so, by which time he would have a job and start to pay his own way in life.

A fortnight into his new existence came the surprise that he actually had found work - at a hotel, helping behind the bar and portering for customers.

It was only 30 hours a week but Matt reckoned that the tips and hotel kitchen were keeping him in food as long as I stumped up the rent until his first month's wages came in.

All was going well. Too well, in fact. For this week started with one of those calls that makes you want to hit your own head against

the wall. He was being thrown out of his digs. There was some complicated excuse about him letting visitors use the shower, but what it all came down to was a failure to pay the rent, on time, in total, or sometimes at all, despite me handing it over each week.

Other Matt 'news' included a claim that someone had stolen £100 of the rent out of his room. Did I realise I was making him live feet from a heroin addict? Did I have any idea how much he was suffering? Well, did I?

By this time, trying not to lose the will to live, it began to sink in that we were back in the bad place where everything is my fault.

Then came the absolute clincher: "Anyway, I've learned my lesson, so you'd better get used to the idea that I'm coming back to live with you."

This, just a week after he'd made the declaration that we were better off living apart as he was learning to manage himself, and having his own address meant there was more chance of him staying out of police cells.

I told him he needed to sort things out with the landlord or find somewhere else to stay - he wasn't returning to Madmum's Cottage.

"You are not listening, mother," he said through gritted teeth. Actually, I was doing just that, close to tears. In the end I simply said 'Sorry' and switched off the phone.