The key to a happy relationship is accepting that miserable patches are unavoidable, according to a report published in the Journal of Marital and Family Therapy. The news may sound a bit familiar – you may be reminded of phrases like “I beg your pardon, I never promised you a rose garden” – but that’s a Noughties report for you. Anyway, you could say, bad times are not only unavoidable in a relationship, they might even be desirable, just as a martini tastes better after a tough day at work. I’d go further. I’d say hardship (in manageable doses) keeps couples frisky.

Human beings, in particular women, need a certain amount of angst or we start to look for trouble. Put me in a romantic hotel with money for shopping, and nothing else to do but eat, drink and canoodle, and I begin to find fault with (in no particular order) my bingo wings, my clothes, my husband, my short-term memory, my teeth, how little I have read, the shower output and so on. Don’t you always have less sex in a swanky hotel than anywhere else on earth? Because it’s just too lovely and easy; there’s too much scope for happiness. And what’s true of the romantic minibreak is true of life generally.

A day of lying around in your cashmere lounge suits, contemplating your gorgeous lives, is infinitely less bonding than a day spent clearing up after burst pipes have destroyed a couple of years’ worth of homemaking. If he can’t find the tap to switch off the mains water, that is not good, admittedly; but if he does eventually, then sets to with a brush and gets lots of plaster in his hair – well, it’s better than the full couples-therapy package. You don’t get that kind of team-building from just being happy.

The bottom line is: happiness is boring, if it is your unwavering state. It makes you complacent and complicated. It stretches on and on with no defining features, like a Californian summer on Valium. Children should be happy; adults need to be strapped to the rollercoaster of life wearing nothing but a G-string, or else they start to worry why they’ve got it so good.

If you are too consistently happy, you will develop an obsession with the precise shade of white in which to paint the bathroom. You will buy more clothes you don’t need. You will spend hours planning holidays to places you don’t especially want to visit, and take too many photos. In the end, the whole process of being happy and showing your friends how happy you are will start to affect your relationship. Misery is private and real. It reminds you who you both are – when you’re not laughing your heads off in your new Mini Cooper.

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