Clever Oliver James. It is he who has identified, in his new book Affluenza, the reason I am in a fever of grumpiness during January (besides the alcohol withdrawal). Apparently, the middle classes are in the grip of a “virus” that makes them place too much value on money, possessions and appearances. We’ve confused the idea that we are expressing ourselves as individuals with the idea of purchasing goods and services, and that way lies only misery.

I had a hunch this might be the case, but I am relieved to be reminded why sales month is so bad for the soul. In the past week, I have bought two pairs of jeans and a framed poster saying, “Peace” — all at half their original price — yet I don’t feel remotely satisfied. It was Christmas a few weeks ago, after all, and I’m still taking stuff back. The whole business is deeply shaming.

And yet I have to take issue with James’s theory that shallow consumerism is bad for us all the time. Provided you have a grasp of your financial limitations (aka “hide your credit card”), there are few pleasures as rewarding as a bit of mad shopping. James doesn’t seem to have taken into account the endorphin rush that accompanies a dash to the make-up counter (you don’t need the lip gloss, but it puts paid to those fortysomething blues in a way that gardening just doesn’t). A lunchtime visit to the Cross (my local twinky boutique) is the equivalent of a slumber party — an hour spent drifting in a girlie cocoon — and if you end up wasting some money, so be it: it’s still cheaper than a spa break.

Occasionally, girls need something fashionable and ruinously expensive to make them feel that life isn’t all about superfoods and school catchment areas. In fact, in my experience, spontaneous shopping is a harmless form of self-medication that beats Valium. Most of my crises have been eased by blundering around among shelves of cashmere or scented candles. Some people swim to ease their pain; some like to talk or take to their beds; others prefer to generate some heat in their wallet — it’s not always about keeping up with the Joneses.

As for the big issue of our obsession with property, women need plans, projects and drama, and I would contend that decor-mania is healthier than an affair. Besides, without the hope of one day living in our perfect house — the fantasy of building out into the dingy yard or of having stair carpets that aren’t sticky with jam some time in the future — most of us would turn our face to the wall.

There are more important things in life, obviously, but these things matter, too, and they keep us sprightly and alert.

Though if you ask me why he needs a plasma screen instead of a standard TV,

I couldn’t begin to tell you.

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