I knew my hosts talked about me afterwards, bonded together by my situation. Poor Pru. How lucky we’ve got each other. It gave them an erotic jolt, and that night they’d make love for the first time in weeks with an ardour that startled them both.

My envy became all-consuming. I can admit it now. Even more than the laughter, I envied the bickering and arguments, because that was so familiar. Whether Greg and I were happy seemed irrelevant by now. I simply envied the normality of what I’d taken for granted. Not trips to Venice, not big things. Just the ‘we’ so casually scattered through the conversations. Just being a couple.

And now the weather was warmer you couldn’t avoid the bastards. I didn’t mind the young ones, of course; it was the old ones who upset me. Walking hand in hand in Highgate Woods; queuing at the cinema. I’d see them in Aldi, helping each other at the checkout—you had to be fast, in Aldi—a practised team, like grizzled, synchronised dancers, loading the trolley for their grandchildren’s visit.

If I’d had grandchildren, it might have been easier. I’d have someone to love. But my daughter, who lived in Reykjavik, was a workaholic with a same-sex partner, and too busy to be pregnant, and my son, who lived in Pasadena, was a computer nerd and seemed to find it hard to relate to anybody, let alone breed with them.

Besides, I suspected that Max, my son, sided with his dad. He’d always been a loner and no doubt understood Greg’s need for solitude. Working in IT suited him fine as he didn’t have to talk to anyone at all. Lucy was more communicative, FaceTiming each week, but I didn’t want to worry her and pretended that I was coping OK. ‘To tell the truth I’ve seen it coming for years,’ I lied. ‘It’s actually rather a relief and I’m enjoying my new-found independence!’

It didn’t help that Azra and I had one of our rows. Azra had been supportive for months, treating me with uncharacteristic kindness, but she could flare up unexpectedly. She probably thought I was recovering and could take it. At the doorstep she’d crossed paths with one of my pupils, and when we sat down in the garden with our tea she launched into an attack.

‘I can’t believe you’re helping these kids,’ she said, ‘someone like you, with your politics. Drilling them with all that stuff to get them into private school! Haven’t they got enough bloody advantages already, the rich little cretins?’ She dredged out her teabag and flung it into the flowerbed. ‘Don’t you feel guilty?’

Of course I did, but I wasn’t letting on. ‘I need the money,’ I said. ‘And anyway, aren’t they just people? I seem to remember you saying that.’

‘When?’

‘About sex.’

‘You’re having sex with them?’

‘No! When you said it didn’t matter what gender a person is. “That’s the last thing that concerns me,” you said. “They’re just a person—who gives a fuck?” You were quite sneery, actually. Quite squelchy.’