Just then another mother from school, Alison, and her dog passed by and the three of us stopped to chat. Now here’s an interesting and bizarre thing, Dr. R: we laughed and chatted as if nothing in the world had happened. We told amusing children/school/doggy stories; I don’t remember precisely which, but there was no mention of the fact that my best friend, the woman at my side, the lesbian, was a husband-fucking harlot. Were Alison to know the truth of the situation – say if in two minutes’ time I were to have stuck a branch deep into Ness’s throat and Alison were to give a police statement – she would never in a million years have believed such a thing possible. Aren’t we strange beings? It was almost as if Ness and I were playing roles in a theatre play and this was an interlude. After Alison left and we carried on walking it would have been the most natural thing in the world for me to take Ness’s arm – I nearly did; I had to stop myself and remember how things were. We waved Alison off and promptly returned to Act Two: wronged wife and remorseful slut.

‘Can I please ask you not to tell anyone?’ Ness said.

I stared at her. ‘No. That’s not up to you,’ I said. Blimey, give her an inch. Besides, did she seriously think I would be broadcasting my own humiliation? I looked her up and down. She looked like shit. If she’d still been my friend I would have been appalled to see her in such a state; as it was, I was just curious. ‘Aren’t you even going to apologize, Ness?’ I said.

She looked flustered. ‘I thought an apology would sound trite.’

‘Well, you might have tried!’

‘Of course I’m sorry, Connie.’

‘No, you’re right. It does sound trite.’ I was aware that I was being cruel, but again, it felt like I was playing at being cruel, as if the whole situation were constructed – the mud, the miserable day just set-dressing. Another day it might be sunny and we might swap roles. Does that sound mad?

‘It’s not going to happen again, I promise,’ she said, touching me one more time and letting go quickly. And suddenly we weren’t play-acting. It was serious. We stood there in the pouring rain and I felt indescribably sad.

‘How could you?’ I said, genuinely flummoxed.

The rain dripped off her nose. ‘I’ve been trying to work it out. I think I’ve been terribly lonely after Leah left and Karl’s just been . . . there . . . so easy to talk to . . . he just, he was so kind . . . and we crossed a line, I got too close with him.’

‘Are you in love with him, Ness?’

‘It was a mistake. It’s finished.’