It’s not so bad being a 1661-er — you know, looking 16 from behind, but 61 from the front. A male shopkeeper called me “Miss” the other day. Then there’s the text I got from my ex in New York, wondering if I could spare him and his boyfriend some of my eggs. How sweet of him. At my tricky age, I mean. And how gallant in contrast to the way Nick, the father of my kids, and the person whom I now live with, always shakes his head and says “enjoy it while you can” whenever that time of the month rolls around.

If only I were 15 years younger. Because lately, I’ve been thinking quite a lot about having another baby. Dreaming about it, actually — a psychosomatic symptom, no doubt, of the huge surge of fertility you’re supposed to get right before the big You Know What. But could I handle being pregnant again? Being so completely and utterly off the fanciability radar? Could I handle being four stone more than I am now? With no guarantee it would come off afterwards? Being middle-aged is bad enough. Being middle-aged and fat is enough to make you bipolar, surely.

I know, I know. You’d think, by the time you reach a certain age, that the obsession with body image would wane. That one’s autumn years were precisely the point in time one should be able to eat shortbread for breakfast and pad round the house in elasticated-waist slacks without feeling suicidal about it. On the other hand, why should that be so? When is the magical Damascene moment when you stop defining yourself, to paraphrase my heroine Jennifer Aniston, by how much you weigh?

There are a lot of things you’re supposed to stop being the nearer you approach fifty, but I don’t feel at all different to the way I felt in my twenties, or even my teens. Certainly I don’t feel any more solvent, scrabbling around every morning for Tube change, stealing £20s out of Nick’s wallet for pocket money and forever having to borrow from the nanny for petrol and wine. My former analyst would have a field day with this, and I can understand why. This perpetual living from hand to mouth, this inability to open bank statements, this almost complete abrogation of financial responsibility is obviously some subconscious desire to be a little girl again. Or a student, anyway.

These and other thoughts were swirling round my head when I took Amanda, the interior decorator whom Nick has hired to do something with the digs-like tip we call home, to trawl round some of our friends’ houses for inspiration. Am I getting poorer or is everyone else getting richer, I couldn’t help wondering as uniformed Filipina housemaids showed us round temperature-controlled shoe cupboards, plasma-equipped bathrooms and Boffi kitchens. Each and every one of them had a minimum of three dishwashers. But then I think even our cleaning lady has two. Having just the one, I have come to the conclusion, is as exceptional nowadays as being the holder of a green American Express card. Which I still am, and, being a 1661-er, quite proud of it too.

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