Just imagine it. A younger lover to fulfil all your physical desires and another, more mature and settled partner to share your domestic bliss, even take delight in running the home and in raising your offspring. Doesn't that sound ideal?Tilda Swinton, 47, who appeared at the Baftas on Sunday with artist Sandro Kopp, 29, recently said of her partner, 68-year-old director and artist John Byrne, "We ostensibly live in the same house, but I travel the world with another delightful painter. The arrangement is just so sane."
A moment's sober reflection brings you to the conclusion that "ideal" is exactly what this is. Surely, no one can be truly content to stay at home while their partner enjoys lust and leisure elsewhere? Surely, a stay-at-home partner must feel jealous?Not according to Byrne, who has told reporters: "We're amicably living together in the same house, under the same roof. It's extraordinary. We love each other too, in an extraordinary way."
Human beings are remarkable for their diversity, and that includes the vast range of relationships we can create and maintain. And the most important ingredient in any relationship is a good matching of needs. That is, the sum total of everyone's needs must be met within the relationship. This is a rarity within any relationship - almost never does one person meet all the needs of their partner. Most of us either simply accept that some of our needs will go unmet, or we fulfil them - usually, the less controversial ones - outside our primary relationship.
Tilda Swinton: Her toyboy, elderly lover and an intriguing ménage a trois
By ALISON BOSHOFF - February 13, 2008 Tilda Swinton stormed the Baftas with her paramour, 29, at her side. So what happened when she took him home to stay with her partner, 67, and their twins? Welcome to an intriguing ménage a trois
There is something captivating and other-worldly about Tilda Swinton; her powder-white skin, as luminescent as a teenager's, her heavily lidded deep green eyes and that shock of incredible red hair.
Even if she were not dressed in an avant-garde gold Dior gown and carrying a Bafta statuette, as she was on Sunday night, there would be a reason to stare.
Indeed, she is so extraordinary that at first you barely register whether there is a man on her arm, and if so who it is.
This week, a handsome German-born artist named Sandro Kopp - 29 to her 47 - was playing the role of consort.
Kopp met her while playing a Centaur on the Chronicles Of Narnia film three years ago. She was the star of the film, the White Witch.
There seems to have been a coup de foudre,and the pair were spotted together outside a gym in Los Angeles last year.
His status as her new man was cemented, then, by his first official red-carpet appearance at her side this week.
Handsome and softly spoken, he trailed behind her discreetly at the official after-party at the Grosvenor House Hotel, and the pair disappeared into the night in the early hours.
Friends say that they plan to attend the Oscars together next month, too.
But the question of who is playing a supporting role to Ms Swinton is not exactly clear cut.
For at home - a spectacular pile on the banks of the Moray Firth - is Swinton's long-term love John Byrne.
And yesterday he revealed that he is very much a part of Swinton's life still.
Indeed, he made it clear that he and Swinton still love each other, and that they continue to raise their ten-year-old twins Xavier and Honor together at their whitewashed home, which is in a secluded spot at the end of a tree-lined road.
This is extraordinary enough.
But there's more.
The twins, it emerges, were with Swinton and her lover at the Bafta's ceremony, and returned to the family home as a group - including Kopp - on Tuesday afternoon.
They were greeted at the door by Byrne, who helped them with their cases.
The unconventional ménage then retired inside.
Kopp, it seems, is staying over in Scotland for a few days, with the full blessing of Byrne, an eccentrically bewhiskered figure who, aged 67, could almost be cast in the role of grandfather.
Who is - ahem! - occupying which bedroom is a rather tricky question which, for whatever reason, Byrne prefers not to answer.
"I wouldn't encourage you to ask anything like that," he growled.
"It's nobody's business. It's our business. It's nobody in the world's business."
It's no wonder that heads turn in Nairn when they see Swinton, Byrne or, very occasionally, Kopp out shopping in the village.
The locals are kept busy trying to work out what on earth is going on behind the closed doors of the Swinton-Byrne residence.
The truth, according to associates of Swinton, is that she is very deeply in love - with both men.
And far from being a passing phase she is said to hope that it continues indefinitely. "All I can tell you," said a London associate of the actress, "is that Tilda is delightfully, extremely happy."
Sandro is her man when she travels - he is an artist and claims to have bases in New York, Paris, Germany, Rome and New Zealand.
He accompanies her when she is filming - indeed he's thought to have been with her when she shot the sequel to The Chronicles Of Narnia in Prague last summer.
He has painted her more than once, and seems quite devoted to this unconventional, highly intelligent woman, who read English at Cambridge and was the head girl of her school, West Heath no less, where she was also an exact contemporary of one Lady Diana Spencer.
But when Tilda goes home, she goes home to Byrne.
Which brings us back to Nairn, which, despite its reputation as the "Brighton of the North", is a small seaside resort town, the kind of place where, as Swinton once said: "Everybody kens yer faither."
North of Inverness, it's a place which has a reputation as a lovely spot for well-heeled folk to retire - rather than a bohemian paradise of free love.
Swinton was this week, though, doing her best to pretend that her living arrangements are absolutely nothing out of the ordinary.
"What arrangement?" she said, exiting a scruffy Land Rover.
"There is nothing to be cleared up.
"What is true is that John and I live here with our children and Sandro is sometimes here with us, and we travel the world together. We are all a family."
Asked if she was sharing her affections with both men, she said: "That is absolutely none of your business."
She added before heading indoors: "John and I have two children; we are together, very happily living in this house.
"Sandro and I travel the world together. What you must also know is that we are all very happy.
"Sandro is visiting now. As you can see we are all putting our luggage into the house together."
For his part, Kopp was a little bemused to be asked about his part in her life.
He said: "I have been to lots of functions - at least a dozen - with Tilda. I sat next to her at the Narnia premiere."
At this point John Byrne, who had been listening to the conversation, butted in to support him, saying: "And that was at the Albert Hall."
Byrne, a playwright and painter, whose TV show Tutti Frutti won six Baftas and who is a star in his own right, added: "Sandro and Tilda travel the world together. I have my work to do here."
What a rum old do. But as we shall see, Tilda is an unsettlingly uncompromising woman. She joined the Communist Party as a student, and said recently that she rejects the "right to pursue happiness" as the heart of the rotten capitalist system.
She has no vanity and has been mistaken - because of her height and androgynous features - for a man ("I should wear more lipstick," she smiles).
When off-duty she proudly sports hairy legs and "gnarled" feet.
She has no television in her house, for fear of making her children "torpid". Instead she prizes joy, creativity and above all intelligence.
She rejoices in her independence and the distance she has travelled from the bourgeois conventionality of her own family.
(Her mother, Lady Swinton, answered the phone at her Borders manor house yesterday and plummily offered the opinion that her daughter's love life was not something about which she could possibly comment.)
One local source said: "She is a different person out here.
"You have this situation where she is running around in an old green cardigan and beaten up car one minute, and the family look like a bunch of tinks to be honest - and then she goes away and it's all stretch limos and all that. It could not be more different."
Swinton met Byrne in 1985. He had designed the set of a play she was appearing in at the Traverse Theatre in Edinburgh. It was an unlikely encounter - Matilda Swinton can trace her paternal ancestry back 35 generations, to the ninth century.
Her father, Major-General Sir John Swinton, is the former head of The Queen's Household Division and Lord-Lieutenant of Berwickshire.
Tilda was expected to make a good marriage - instead she embraced academe and the theatre, and along the way questioned the values of capitalism.
Her early work was notably experimental, particularly the play in which she acted the part of a woman pretending to be a man, complete with a plastic penis.
Byrne, meanwhile, was raised on a slum estate in Paisley and worked in a paint factory, which he later immortalised in the Slab Boys trilogy.
An artist of distinction, he is at least as much of a celebrity in Scotland as she is, and famous for creating Billy Connolly's banana skin boots if nothing else.
Swinton clearly made an impression on him, though - he wrote a part in the TV series Your Cheatin' Heart for her. By 1990, he had left his wife, Alice Simpson, and their daughter, and moved to London to be with his flame-haired girlfriend.
Her big break came in 1992, when she took the title role in the art-house hit film Orlando.
By this point she had begun her collaboration with film-maker Derek Jarman; they made nine films together before his death in 1994.
The following year she went on display in a glass box at the Serpentine Gallery as part of a piece called The Maybe, which seems to have been a statement of mourning for Jarman.
Three years later, her twins arrived.
She told an interviewer previously that she had been longing for babies for several years but had not, as such, decided to try for a family "but it's like they get themselves born".
Soon afterwards, she, Byrne and the babies moved to the Highlands.
It was something of a return home for her, as the Swinton family home is in Duns in Berwickshire, and she has spoken of loving the isolation there.
It also appealed to her rebellious side.
"Scotland is not a middle-class country and it could never be made to be. It will always be independent, its sense of itself is inspiring," she said.
Both she and Byrne did their best to fit in. They took Gaelic lessons and sent the children to Gaelic nursery.
Now they attend the nearby Steiner school, which does not begin any formal instruction until the children are six-and-a-half, and places great stress on creative inspiration rather than formal learning. Swinton wryly describes it as "hand-knitted" in ethos, and she is one of the parents who helps to maintain and clean the school.
The children have had an idyllic childhood, going on camping trips with their parents, running through the long grass and romping on trampolines.
Swinton says that Byrne is an "exceptional" father and that they remain fully committed to the "project" of raising them both.
"We love our children and our children love us," said Byrne earlier this year. "The rest is business."
As the children have grown older, she has fully re-entered her career in movies, starring in art house projects like Young Adam and more conventional fare such as Michael Clayton. For her role in The Chronicles Of Narnia she requested that her corset be laced so tightly that she could only rest propped up on a stand between takes.
"I am a soldier," she says, and she does come from a long line of upper-class military men.
"I live a soldier's life when I'm working. That's how it feels to me, except I've got a slightly greater chance of survival."
She also, now, has Sandro to keep her company while she is away. One associate said that his role was almost that of 'her personal assistant'.
Certainly, he would be unwise to expect a happy-ever-after scenario from this relationship, as Swinton does not believe in it.
"Loneliness is the deal," she said in a recent interview.
"Loneliness is the last great taboo.
"If we don't accept loneliness, then capitalism wins hands down. Because capitalism is all about trying to convince people that you can distract yourself, that you can make it better. And it ain't true."
Maybe she can say this because Byrne is always there for her when she returns. She relishes the split.
"The split is important," she says.
"I could call it a double life but actually it's really quite integrated," she says.
"It's just a working life - I go away and then I come back. John is always at home."
Byrne, it seems, does not try too hard to make sense of what is going on, but just holds on to the idea that they have always been "the best of chums" and will continue to be.
He told an interviewer: "They're frightening creatures, women, they really are. An extraordinary species.
"We really don't have a clue."