For the record, I never, ever suspected that Rachel was obsessed with me. She worked at Moorfields before you started there. Of course, I don’t remember seeing her there. Tilly says she never suspected anything either. She said Rachel talked about me quite a lot, but she didn’t think anything of it.

Somehow, I unwittingly attracted a psychopath, one who became fixated on me for reasons I will never fully know or understand. I read that approximately one per cent of people are psychopaths. In London, that’s 80,000 psychos. I think only a small number of them are dangerous. I was unlucky. We were unlucky. As were Karen, Sasha, Harold, Victor.

There was a profile about her in the paper. Like us, she was an orphan. But she was put into the care system, going from foster home to foster home. She kept running away, couldn’t settle anywhere. There was an interview with one of the foster mothers, who said that Rachel – or Tracey, which was her real name – became obsessed with one of her ‘foster brothers’, tried to poison him when he rejected her advances. This woman said she used to bring home stray cats, keep them in secret in her room. Once, she found that Rachel/Tracey had broken this cat’s leg so it couldn’t run away.

It turned out that her dad did similar things to her mum. Beat her so badly that she couldn’t leave the house because he was afraid she would leave him. One day the mum tried to escape but he caught her and killed her, then committed suicide. Rachel/Tracey saw the whole thing.

I can’t help but hate the woman Tracey became, but I want to cry for the child she used to be.

I think Rachel had been patient, happy to watch me for a while, but when I got together with you it seriously accelerated her crazed actions, panicked her, made her decide that she had to eliminate all the opposition.

Certainly the easy thing, though it pains me to write this, would have been for her to kill you. So why didn’t she?