Meghan studied the book — an instant bestseller when it came out in the mid-Nineties — so thoroughly she was able to recite passages off by heart.

According to Ms Priddy: ‘Meghan used to quote The Rules all the time and really put it into practice with a number of her boyfriends.‘She was never without a boyfriend for more than two or three months and always striving to have someone by her side.

As one figure close to the Royals told me: ‘It’s a horrid little betrayal, but it won’t damage her reputation.

She’s not a virginal bride like Diana, who was only just out of her teens when she married Charles, but a mature woman of experience with one failed marriage behind her.’The disclosures have come from Ninaki Priddy, once an inseparable friend of Meghan to whom she had been ‘like a sister’. Since Meghan’s engagement to Harry she has spilled just about every intimate bean of their 30-year friendship.

Yet amid the chiselled ex-actors and sports stars who are reportedly former beaux, the figure of Simon Rex stands out.

Posing languidly stretched out naked on a bearskin rug, an unlit cigarette dangling from his mouth and with only a puppy to hide his modesty, he seems an unlikely suitor in the life of the poised young woman who next week will become Her Royal Highness and daughter-in-law to the Prince of Wales.

While the photo alone must be embarrassing enough, it is the back story of the model-turned actor, who made his name in the Scary Movie franchise, that really adds to her humiliation.

For Rex — born Simon Rex Cutright and now a 43-year-old comedian and rapper using the name Dirt Nasty — is a former star of ‘adult’ films, the Hollywood euphemism for porn movies.Instead, any lingering hopes she may have had that her past life would remain off limits as she completes her transformation from Hollywood starlet to royal princess must surely now have vanished.If it’s any comfort, the Royal Family will scarcely raise an eyebrow at the revelations.She liked the idea of being part of a team and having a domestic life.’Ms Priddy adds: ‘Any relationship that she was in, there was always an element of marriage in the back of her mind.’ Meghan, she says, would quickly be thinking about what the relationship would be like in ten years time.That surely cannot have been the case with porn star Rex.He was already a successful model appearing in ads for Calvin Klein, Versace and Levi’s while Meghan was still a year away from her first regular-money role as a ‘briefcase girl’ — holding up a case full of cash — on game show Deal Or No Deal.