It isn’t often that you feel the swelling of national pride, but anyone who watched Tilda Swinton receive her Bafta will surely have felt a twinge of, “Only we make ’em like that.” There was that white skin, the regal bearing, the hobbling Dior dress, not to mention the film she was nominated for (smart, conscience-pricking – her usual fare). And she’s naturally beautiful at 47. No Botox or exclusion dieting for our Tilda – just plenty of Scottish coastal air. She lives in Nairn with John Byrne, the father of her twins; the children are at a Steiner school, and you won’t find a PS3, a Nancy bag or a gas-fired barbecue within 10 miles of their remote home. (Don’t you love her? So refreshing! So us at our best!)

There is one other detail: her regular companion, Sandro, 29. Ah, yes. It’s not just that she embraces bohemianism in the sense of barefoot children and no TV – she embraces two men at the same time. And this is where the English eccentrics fan club put their hands up and cry “Enough.”

The British are bohemianphiles in every respect, except sex. We love dogs at the table, we appreciate gardening in the nude and a casual approach to heirlooms. We indulge mild madness, drunkenness, squalor, individual style (Withnail and I has cult status on account of all the above). But we have yet to swallow the idea of an open relationship, even one that has lasted 18 years and works well for all involved. Swinton valiantly tried to put a creative spin on her living arrangements when the story blew up after the Baftas. (“We ostensibly live in the same house,” she said of her relationship with Byrne, “but I travel the world with another delightful painter.”) It was a wasted effort on her part. Funny Viktor & Rolf clothes, yes, we see. Taking a “companion” 18 years your junior, no, we don’t.

These moments will crop up, now and then, to remind us how confused our standards are. The average Hollywood child has to get used to several “parents” in a lifetime, plus stepbrothers and -sisters and, increasingly, a rainbow spectrum of adopted siblings. (I’m focusing on the children because, presumably, it is their feelings that the shocked majority are concerned about.) Either mum or dad will be in rehab at some point, and in acrimonious litigation with each other, sooner or later. There will be lots of nannies, houses and new partners coming and going. By modern standards, the Swinton set-up is remarkably secure and uncomplicated.

Shall we just admit that a 47-year-old woman stepping out with a man who isn’t quite 30 is a threat to many (though not to Byrne). As long as we don’t think it’s a straightforward issue of morality, because that would make Angelina and Brad a “better” example than Tilda and friends, which would just be depressing.

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