Love, honour – and annoy

Spring, and 'tis the season not for rising sap and blossoming ardour, but for that still more time-honoured romantic phenomenon: unreasonable behaviour (UB).

For, behold, fessing up to a spot of unreasonableness allowed Formula One boss Bernie Ecclestone a positively boy-racer divorce. The behaviour in question centred on his workaholic, 18-hour day tendencies. However, it is entirely possible that his ex merely woke up one morning and found it unreasonable to be married to Ecclestone.

And it's not just married types. Everybody's favourite desperado-next-door, Jennifer Aniston, is believed to have dispatched warbler John Mayer on the same grounds. The issue appears to have been that, while too busy to be in touch with his inamorata, Mayer was never too hectic to drop his addiction to social-networking-via-haiku site Twitter.

Recent gems charting their off/off relationship include his immortal: "Half of my heart is a shotgun wedding to a bride with a newspaper ring/HOMH is the part of a man who knows he's never really loved a thing". Not unreasonably, this made the Friends star retort that it was, like, totally over. Shortly after said dumping, Mayer's Twitter update lamented: "This heart didn't come with instructions." Mayer is 31.

Ah, unreasonable behaviour – can't live with it, can't break up in Celebrityville without it. For, while we civilians may behave unreasonably, unreasonable behaviour as a lifestyle choice is a VIP preserve.

The reason is clear. When slebs want something they want it now: a smoothie, an African nipper, a divorce. Without unreasonable behaviour they will have to wait two years for a decree nisi – years that might usefully have been spent totting up other marriages. Instead, with a spot of unreasonableness, it's adios, re-route the offspring, and find yourself the requisite Brazilian.

The beauty of UB is that it can be all things to all men; and, more specifically, a certain type of woman. Edith Wharton got this spot in The Custom of the Country, where her heroine – the sublimely monstrous Undine Spragg – defames not one, but two paragons of former husbands with the charge.

For although violence, abuse and the like may be a factor, what is more usual is a series of ostensibly blameless defects the cumulative effect of which is the mother of all hissy fits. Moreover, as with Spragg, the boot may often appear to end up on the wrong foot.

Word on the street is that Madonna alienated ex-husband Guy Ritchie by her refusal to eat normal food, subscribe to a normal religion, penchant for smothering herself in $800-a-jar unguents and rage when he would not concede that she was "bigger than Jesus". Accordingly, it comes as no surprise to find the singer divorcing him for the unreasonable behaviour that is watching television, enjoying the odd roast, and going to the pub.

Here, too, lies another truth about UB: all too frequently the behaviour in question is what the complainant appeared to sign up for. Thus, when Paul McCartney accused Heather Mills of the unreasonable behaviour of being rude, argumentative, and more than a little screwball, the collective response was: "Really, Sir Paul, d'ya think?".

Moreover, the Macca proceedings illustrate a further crucial dictum: canny divorcees keep it uncontested. This is vital in order not to devolve into: "You wouldn't fetch my leg so I could take a leak" type jiggery-pokery.

Otherwise, the form is clear. Keep things vague: "We have to maintain different continents". Stick to the correct platitudes: the behaviour should not be affecting one's health, yet "continuing". And, where possible, let benevolence reign – paradigmatic example, the ex-Mrs George Galloway's pointing to his friendships with other women, rather than, say, that leotard.

Meanwhile, so much is unreasonable behaviour a rite of passage for the contemporary celebrity that post-modern slebs – those famous merely for being famous – fall over themselves to get a piece of the action.

Accordingly, 90-second "closure" for UB became the most compelling claim to fame on the part of Big Brother poster girl Chantelle Houghton and the sometime pop singer she married, Preston of the Ordinary Boys. While Cheeky Girl Gabriela Irimia, although merely a fiancée, got to ditch MP Lembit Opik for being both dictatorial and not terribly adept at touching her bum – proof that a charge of unreasonableness may contain much by way of reason.