We were watching Top Gear. I was sitting on a wobbly fold-up chair at a rickety garden table in a newly decorated, though otherwise empty first-floor flat. The garden furniture was there because the estate agent said it was better to have something in the sitting room rather than nothing at all, otherwise the place might have a desolate, depressing air that might put the viewers off. My boy has borrowed the flat from a friend for a couple of days while he considers his options. He, poor lad, was sitting at the table also, feeling the heat and desolate with grief. But he was maintaining his dignity. On the table was a flimsy floral tablecloth, and on that a copy of the Sun newspaper.

‘She’ll come round in a minute and you’ll look back on this and laugh,’ I said. He focused his brown eyes sceptically on mine for a moment then returned them to the irrepressible Jeremy Clarkson. He and his fellow petrolheads, and the adoring audience, which was massed and grinning around him, didn’t appear to have a care in the world, nor did they seem to have the capacity to have a care in the world. There was a very beautiful, sexy, beaming woman in the front row, as there usually is, and I suddenly desired to be her, or to be united with her, with a violent desperation that surprised and appalled me.

The heat in the flat was stifling. Every window in the flat was flung wide open to invite a breeze — though none came. The three musketeers were in Spain racing supercars around the empty streets of a half-finished housing project and mucking about in a deserted brand-new airport. But my thoughts kept straying.

I looked down at my narrow, unfamiliar, sandalled feet and studied the broken nail on my big toe. Then I studied my knobbly knees, one crossed over another, and let my eyes wander over the grass stains on my black Adidas shorts. I’d put them on the wrong way round again, I noticed. Misled by the position of the side pockets, I put them on back to front probably nine times out of ten.

The flat was the only private property on a purpose-built estate for servicemen and women. Servicemen were strolling back and forth on the tarmac below with their shirts off. Someone was having a barbeque. Smoke curling from an end-block garden told where. A man with the toned body of a fitness fanatic, and a can of Red Stripe dangling from his fingertips, walked slowly around my car — an old Mercedes pillarless coupé — admiring it, I think. There aren’t many of these left in Britain now. The front is a bit boxy, but viewed from the side the car is as aesthetically pleasing as a Turner. A security patrol van cruised by at less than a walking pace. The driver’s arm was hanging out of the window. The arm raised itself a few inches to acknowledge the car enthusiast and fell back again.

‘I’m not having it,’ I said. ‘And neither should you be!’

My boy regarded me calmly and candidly for a moment. The look was meant to suggest that of the two of us at the table it was I who needed to adjust my understanding to the present reality, and not him. ‘I know her. It’s over,’ he said. Then he took his mother’s big brown tragicomic eyes back to the television screen.

Whatever else is happening in my life, I’m having a love affair with one of his children. (The other lad is contentedly absorbed by his inner world and shows few signs of wanting to transfer to the outer, even at two.) From a purely selfish perspective, my future happiness was as threatened as my boy’s. Perhaps more so. And this was the exact moment I realised that this was the reality, and that my world had changed. Up to this point I had lightly dismissed the recent split as temporary; a hackneyed scene from a popular, much repeated period drama, in which I’ve played a sagacious and kindly old nincompoop with his wig awry.  Now I was frightened. ‘Well, I’m not having it,’ I said.

It sounded hollow. My boy stood and went into the kitchen to look for something to use as an ashtray. I could see him through the hatch rummaging through a wall cupboard. Then he returned to the table with the glass lid of an ovenproof dish and placed it between us. I felt the stirrings of a breeze enter the room and fan my cheek on its way past. My boy reached for his pouch of smuggled tobacco. The Top Gear audience roared with sycophantic laughter. Outside, a dove called soothingly.