A bunch of mothers stand on the touchline of a football pitch at a mixed Catholic prep school near Pangbourne, Berkshire, one sunny afternoon last week.

In our Boden coats, Hunter wellies and last season’s Uggs, shouting “Come on, Rupert, up the line,” and “Good save, Freddie,” we must look the picture of middle-class smugness, with our labradors snoozing on the back seats of the Volvos in the car park.

But then the middle classes have always been terrifically good at keeping up appearances.

At half-time I ask the group whether they’re having a rough time money-wise. After all, it’s self-assessment tax-return week – the high point of penury in the calendar year – that has left many of us up in arms and down at heel, feeling that the government (which leaves us with just under a third of our gross income after we’ve paid tax, National Insurance and housing costs, compared with 34.5% when it came to power) is bilking us of more of our hard-earned money than ever, and frittering it on creating wellbeing officers in marginal Labour constituencies, and ID cards and yet more computer systems that don’t work.

Last week also saw the middle classes anatomised at length as “the coping class” – not for digging for Britain, not even for finding 100 ways with mince – but for our capacity to withstand the expanding calls on our dwindling trickle of what is still, for some reason, called “disposable” income: from childcare to paying for the care homes of elderly parents and everything in between.

Meanwhile, Hiscox, the insurers, revealed that couples who earn a healthy £88,000 between them can now be accounted as the “working wealthy”, because – groan, do I really need to explain? We all know what it’s like patrolling the past-sell-by-date shelves for bargain yoghurts (minus lid) and Oxfam for designer cast-offs (stain on sleeve), even though we earn masses more than our parents (and most of the rest of the UK) and yet we never seem to have any money.

So let’s get back to the Berkshire touchline, to the sun, the sport and the belt-tightening mums, before the final whistle blows.

“We’re going on holiday, but it’s for one week instead of two,” said one, in answer to my general query.

“We’re going to Devon on a family adventure holiday,” said another, naming a residential coastal centre that my daughter’s day school uses for its trips. “I’m renting out two rooms in my house for extra cash.” “I’ve had to take a full-time job as an admin assistant to pay the mortgage, but I’d rather be a nurse.” “My husband’s car’s three years old now and he usually trades it in after one.” “I can’t afford Waitrose any more.” “I never buy fashion any more, I buy one or two classic things I think will last.” “I used to buy designer, now I don’t even buy classics, I’m down to catalogue.” “George’s fees are being paid by the Bank of Mum and Dad.” “I got our electricity bill today, it was almost £500.”

And so it went on in a crescendo of financial decline, the daily struggles and sacrifices of the heroic coping class, until tea, when the headmaster of the Oratory prep, Richard Hillier, summed it up with the words: “My feeling is that parents are quite stretched at the moment, even those on really quite high salaries.”

Of course, being competitive, I joined in and tried to win the “I’m poorer than you” contest that is now being played even more fiercely than Scrabulous in Aga kitchens up and down the land. But as one jolly mother was telling me that she had to choose between sending her son to public school and a conservatory, and another telling me she was skiing this year (though on the school trip, she added hastily), and another was saying that, actually, things were pretty good because her husband worked for the oil industry (Shell has just reported a record annual profit for a UK listed company), I started wondering: what if we’re not the coping class, but the moping class?

Moping because we can’t afford the luxuries to which we think, as educated middle-class people, we should be entitled, such as new clothes and holidays away from our million-pound houses (there are now 88,000 of these), and our expensive Dualit toasters? And I also thought, what on earth would Mrs Thatcher think if she could hear us?

After all, one answer to the big question of the week, namely “Why do we all feel so damn poor?”, is because 3.7m of us are paying the top rate of income tax, which is 40% on everything above £39,825 (while the super-rich have at times been paying just 10%, by disguising income as capital gains – heigh-ho, but that’s another column).

But it’s also because we borrowed too much money on our mortgages and can’t balance the chequebook. Hard not to, house prices being what they are, when it came to buying our homes. I can almost hear Mrs T saying it: our eyes were bigger than our wallets.

According to the Family Expenditure Survey, 50 years ago outgoings on rent or the mortgage soaked up just 8.7% of the weekly household budget. Now it’s 20%.

These figures looked okayish when the housing market was taking off like a Harrier jump jet, but now the rise has stalled and mortgage repayments are rising steeply. So the prospect of negative equity and repossessions is again stalking the land, just as the bills are coming in, taxes are rising and multiplying, and the music has stopped on the money-go-round of the City.

I’m not sure this is much of a silver lining, but maybe all this money unpleasantness will bear fruit for a post-credit-crunch generation. The days of cheap money, 100% mortgages, inflated lifestyle expectations and obscene bonuses are over, and the days of lower taxes, fiscal stimuli, renting, saving and prudence may finally – 10 years too late – be about to begin.

- Speaking of dosh, isn’t it beyond imagining the things some people do for money? I’m thinking, of course, of the new Jerry Springer vehicle Nothing But the Truth, where contestants have to answer killer questions crafted by friends and family to humiliate them, such as “Do you wear a weave?” or “Have you ever touched tongues with your dog?” Contestants are hooked up to a lie-detector test. So as long as they tell the truth, they make money, but if they lie they lose all their winnings.

Obviously confrontation and desperate self-abasement underpin most shame-free telly formats, but what is peculiarly unpleasant about Nothing But the Truth is this: it reminds us that what keeps us together is not ruthless honesty, but vague fibbery.

Applying a don’t-ask-don’t-tell policy when it comes to the deal-breaking questions in any relationship, such as “Do you pay for sex?” or, er, “Have you ever hired anyone to kill your husband?” (a real question on the Colombian version of the show) actually preserves relationships.

It’s brutal candour that destroys them.

rachel.johnson@sunday-times.co.uk

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