There is talk that the most environmentally aware marriage in showbiz may be showing signs of strain. The usual reasons have been trotted out: Gwyneth Paltrow and Chris Martin are not often in the same country. She’s doing parties, he isn’t. But none of this would be worrying if it weren’t for the huge and highly visible incompatibility at the heart of their union. She’s a bow-at-the-neck designer dress, poker-straight hair and lipstick sort of woman. He’s an unshaven, combats-and-anorak man in a faded fair-trade T-shirt. (Gwyneth has done combats, but with a Clements Ribeiro top. When she does scruffy, it’s a bit like Hillary Clinton doing cosy: the effort involved makes everyone feel tense.)

So, Gwyneth and Chris are style opposites. It doesn’t sound like a big deal. You’re probably thinking, “Pfff, so what?” But style is quite a reliable indicator of what you value in life. (Which is why it is okay to dislike, on sight, women who carry Botoxed python bags and men who wear striped shirts with white collars.)

Gwynnie is American Wasp aristocracy: poised, naturally blonde, used to rubbing shoulders with the Establishment, the sort of girl that Ralph Lauren drools at the thought of dressing (and did dress, memorably, in princess pink for her Oscar win). Chris, on the other hand, is a down-to-earth bloke: the type who eats with the crew, writes everything he needs to remember on his hand and gets bike-chain grease on his tracksuit bottoms.

Do you see where this is going? Gwynnie and Chris don’t just look different – they may be looking for different things as well. There is a bit of Gwyneth that wants ozone-no-object glamour, shallow company and lots of attention (you never get over that stuff). Meanwhile, Chris wants to build a tree house for the kids, then have a barbecue (more of a fire between bricks) and ask his mum and dad and the neighbours to come. Seriously. You can tell. Just from the clothes. Gwynnie could ride a bicycle round London, but it isn’t really her. Chris could spend August on Tom Ford’s yacht, but it isn’t really him. They are not a natural fit.

Those who do share a similar aesthetic tend to stand a better chance. Every time they look at each other, they think, “Mmm, me”, as opposed to, “Eeeuw, so not me”. Look at Brad and Angelina: with all that designer utility wear and tattoos, they’re like a walking DKNY ad. Jen was always such a steady girl next door – in her figure-complimenting tops and butt-hugging jeans – it couldn’t have lasted. Mick Jagger and L’Wren Scott are another meant-to-be style couple – controlled, sleek with a twist – Jerry’s look was just too . . . needy. Anyway, here’s hoping it’s something that a stylist, if not Relate, can sort out.

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