I feel disproportionately saddened by the rumours that Madonna’s marriage may be on its last legs. According to reports last week, she may have approached the divorce lawyer Fiona Shackleton, as in Prince Charles and as in Sir Paul McCartney. (Ms Shackleton’s reputation precedes her: when Heather Mills threw a glass of water over her in court in March, you could hear the whoops and cheers from divorcées living in drastically reduced circumstances all over London’s smarter boroughs.)

Calling in the famously effective Shackleton could be rather a sledgehammer/nut approach, since friends of the couple say the split is as amicable as such splits can be — it is described as a petering-out rather than anything more dramatic — and that Madonna, 49, doesn’t foresee Guy Ritchie, 39, behaving in anything other than an honourable fashion when it comes to money (they are said to be worth £300m).

The couple have a seven-year-old son, Rocco, and an adopted son, David, who is nearly three. There have been mumblings about the possibility of adopting another child, and how the stress of that (she was said to be keen; he, less so) may have damaged their relationship. Madonna also has an 11-year-old daughter, Lourdes.

Anyway: I read about this at breakfast feeling weirdly despondent, which is rather mad, since I don’t know Madonna, and since celebrity divorces are two a penny. But for women of my generation she has been a constant presence, in all her various incarnations and reinventions, from ambitious, squeaky sexpot to global superstar.

If you’re the right age (fortysomething), it is also true to say that she has held up a mirror through the decades. We watched her cock-ups and her triumphs: the path wasn’t always smooth, and we really cheered her when the story seemed to have such a conclusively happy ending — not least because her happy marriage hinted at the possibility of our own lives going that way.

Following Madonna’s progress is like mapping out all the memorable things about growing up over the past 20 years or so. She went through an exaggerated version of all the stages of late 20th century girl/womanhood, from agent provocateur to credible role model, from self-styled slapper to mother superior, from ditzy-seeming young woman to thoughtful middle-aged one, via all the brilliant stuff she did in between (I don’t care what anyone says — I thought her book Sex was a work of genius; we could do with a few more women who aren’t scared of being sexy and disconcerting men at the same time. The alternative — on a bookshelf near you — is woman as victim, woman as insipid little thing who needs a man’s lustful gaze to make her real).

Madonna led a creative, interesting existence, and then she settled down — but she reinvented even that. Before Madonna, female celebrities who had children never talked about it, as though reproduction were some weird, shameful female urge that got horribly in the way of being sexy. Instead they reappeared wearing Peter Pan collars and pastel colours and talking about soup. But Madge took to motherhood like a duck to water, didn’t let it stop her dead in her tracks, didn’t suddenly turn into a diluted version of herself. She gave the rest of us hope.

When I was writing my first novel, nearly 10 years ago, I made my narrator ask herself: “What would Madonna do?” at times of crisis. The answer, which usually centred on not taking any crap from anybody and getting on with it, was inevitably the right one.

There was an interesting review in The New Yorker the other week, of the film of Sex and the City, in which the writer lamented the feeble and, he thought, fairly tragic and unevolved fact that none of the women in the movie is deemed to be happy unless she has a husband (apart from Samantha, who doesn’t count because she’s a gay man). I’d hate to tar Madonna with the same brush and suggest that her life is now one long tunnel of gloom because she’s mislaid her husband, but I can’t help thinking that if Madonna, with all her determination, tenacity and ambition, can’t make a marriage last beyond seven years, what hope is there for the rest of us?

No wonder that, according to figures released last week by the Office for National Statistics, married people are now in a minority. Most over-16s are single, divorced or widowed. You wouldn’t think it, would you? But it’s true.

Of course, marriage isn’t the be-all and end-all, but a failure is a failure, and it is painful to see determined women unsuccessful in marriage, especially where there are children involved. What is especially irritating in this case is the inevitable conclusion people will reach: that a powerful, successful woman is an emasculating thing, hard to live with, too ambitious, too forceful, too much like hard work, which is another way of saying “not meek enough”. That is really depressing. Where are all the happily married powerful women, I’d like to know. I can think of a few, but they all work very hard at pretending to be a great deal sillier/more stupid/more benign than they are. That is even more depressing.

I expect Madonna has more pressing issues on her mind than what to do next in terms of her role-modelhood, and the fact her fans feel left in the lurch, sad at the lack of a happy ending, isn’t top of her list at the moment. But for what it’s worth, I hope she eventually does what she has always done, and lobs another reinvention into the mix. Someone needs to buck the lamentable trend and show the world that being a single middle-aged woman isn’t the miserable, depressing living death that it is invariably painted as, each day being yet another futile search to find a man, any man, to give life meaning. It’s such a load of old cobblers.

Madonna is in her prime, well off, healthy, fit (and then some), surrounded by lovely children and perhaps soon to be free of the dramas and stresses of marital strife. Wouldn’t it be wonderful if she seemed happy? If she didn’t rush to find a bloke, but just sort of pottered, hung out with her children, worked, travelled? Wouldn’t it be wonderful if she just . . . liked it? It would certainly be her most radical reinvention to date — Madonna, the happily single. And, as ever, she’d have her devoted band of greying female admirers cheering her right on — cheering quite loudly, I expect, and giving thanks, as ever, for her telling it like it is.

india.knight@sunday-times.co.uk

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