Thrift is the new Ab Fab

Out of the mouths of babes. "Mummy, let's go. It's too expensive in here." We were standing in Topshop viewing size 6 tweed miniskirts when these words popped out of my 11-year-old daughter's mouth last Thursday afternoon. I nearly fell over.

Six months ago, a trip to Topshop would have been the ultimate treat for my little girl and her friends, but now all they want is to trawl around Primark in Hammersmith. This summer, Primark is where she found a fantastic cotton Fifties print skirt - the height of fashion - for about £12. That's half the price, or even less, of Topshop, which I automatically used to look upon as fashion's bargain basement. So now, educated by my own child, I've been taught something new about saving money.

And I have to say, I'm more and more in the mood for that. I've lost the feelgood factor. Clever as my daughter is about spending her pocket money, she doesn't (yet) understand that she is part of the great price-deflationary trend that is about to squeeze our British high-street retailers by the balls.

Nor does she know that, in the past month, our home in the Brook Green area has possibly lost a notional £10k in value, and our mortgage will be going up some time soon. Or that when I look at her, and imagine for a sickening second what it's going to cost to put her and her brother, 14, and sister, eight, through university, that tweed skirt retailing at £24 flies back very swiftly whence it came, unpurchased.

These are the kind of emotionally driven financial calculations that are going on in every family like ours now: the micro-panics that stir a macro-economic trend. With the first shiver of autumn, could it be that long-term realities are finally interfering with the addictive mechanisms of short-term gratification?

If so, it's about time. Britain's orgy of overspending and over-borrowing has to stop. We have to stop - I have to stop being so dumb with money. The British Retail Consortium blamed weak August high-street sales on the weather (as it always does), but I think something else is going on.

The signs are that the brakes are already being applied in the nation's households. Polls indicate 35 to 50-year-olds are cutting back on spending and borrowing, scared of the coming home to roost of their worst nightmare: the terror of combined interest-rate rises and falling property values. No wonder Primark's looking better by the day.

The prevailing psycho-economic wisdom of our times is that when people "feel good", they spend money. But maybe, now, just the opposite sensation is becoming more like it: how about feeling good about not spending money? Or at least, not quite so much, especially while you're not even noticing. Always ahead of the trend, I can recommend this new potentially fashionable thrill. This year, one of the most enjoyable 10 minutes I've spent was when I cut up all the store cards that, apparently without my behest, had taken residence in my wallet. Snipping through the Russell & Bromley card, the Tesco card, and, yes, even the Amex, too (blimey, member since '85!), felt like entering a new era.

I can't exactly swear that I'll be exchanging Prada for Primark on a whole-life basis, but the principle is there. Balanced against what I'll be paying out in 10, 15, 20 years' time, it's only sane to ask: is it really worth it?

Knowing I belong to the lucky generation that will have to work till we're 70 in order to eke out a basic living is also beginning to bite home. Yes, like all the original Eighties Yuppies I went for the exciting private pension option - now worth nought. That's the fear that wakes me at two every morning these days. At those watches of the night, I remember the excesses of the Nineties. For Christmas 1999, we blew £10,000 on a family holiday in St Lucia. (Why? The children hated it. Now it's strictly Cornwall.)

Sometimes my mind runs guiltily over the contents of my storage wardrobe, too. Will the tiger-stripe Fendi Baguette I spent £600 on in 1996 match that value if I keep it long enough? Who was I when I bought that purple £700 Chanel coat-dress, circa '92? A power-dressing optimist, that's who.

We used to eat out all the time, too - and when we didn't, it was prepared meals from M&S. Now it's organic stuff from the farmer's market and my husband's cooking at home (usually much better than eating out, actually). I can't say it's actually about "downsizing" or old-fashioned scrimping. It's just that it doesn't feel clever or stylish to throw money around any more. Admittedly, that still doesn't stop me spending unconscionable amounts on anonymous looking clothes from Martin Margiela or Comme des Garçons on impulse, but at least I do stop for two seconds before confirming to myself that I really am going to wear them. And I do, honestly. All the time.

The trouble is, whatever we do, our generation - the middle-aged - has it coming to us, down the line. Breaking the excess spending habits of the past 20 years won't be easy, but somehow we've got to do it. If only we can make it look cool, we'll have it cracked.