For Autumn Kelly and Peter Phillips, it was love at first sight. They met at the 2003 Montreal Grand Prix, where Phillips was working for Williams Racing, an encounter he described as "fate". Only several weeks later did Autumn, a Canadian management consultant and McGill alumni, discover that her new boyfriend was, in fact, the Queen's grandson and, at the time, 11th in line to the throne. "Oh, Autumn! What have you got yourself into?" exclaimed her mother, Kathleen – but Autumn was not to be put off.
Soon, she was living with him in Kensington, and in a cottage on Princess Anne's Gatcombe Estate in Gloucestershire. When Peter proposed a few years later, after seeking permission from Autumn's father, Brian, an electricity company executive, the blushing bride-to-be told the Telegraph: "I looked horrible in my wellies with wet hair. I said 'Yes' straight away, though." What could possibly go wrong?
Yet, 11 years after their wedding in St George's Chapel, Windsor, the Phillipses have announced that they are separating. The Queen, who has always had a soft spot for her eldest grandson and his pretty Canadian wife, is said to be devastated, while the rest of the country is in shock. No one had their money on Peter and Autumn as being the first of the younger royals to split. In public, they've long been the golden couple, a picture of solidarity at Troopings of the Colour and royal weddings, with their two blonde daughters, Savannah and Isla.
According to a statement issued on their behalf, however, a separation is now "the best course of action for their two children and ongoing friendship". At their 2008 wedding, Princess Eugenie – who went on to marry wine merchant, Jack Brooksbank – read William Shakespeare's Sonnet 116, which describes love as something that "looks on tempests and is never shaken".
But the deterioration of the Phillips' relationship is yet another example of a royal marriage involving a commoner that has failed to go the distance. As the children of divorced parents – Peter's mother split from his father, Captain Mark Phillips, in 1992, while the Kellys divorced when Autumn was eight – Autumn and Peter were always statistically more likely to divorce themselves.
Yet as part of the Royal family, their chances increased ten-fold. Three of the Queen's four children are now divorced; her sister, the late Princess Margaret, saw her high-profile union with Lord Snowdon dissolved in 1978. If this trend continues, it is probable that only a handful of the new generation of royal marriages will survive.
Is the problem that commoners are just too lily-livered to cope with the rigours and responsibilities of royal life? Anthony Armstong-Jones, the photographer who married Princess Margaret in 1960, was unable to give up his photography and focus on the job in hand. Meghan Markle, an actress used to being in the limelight, lasted just 18 months in her royal role before she ditched the title for a quieter married life on the other side of the Atlantic. As Prince Harry claimed: "There was really no other option…"
Even Tom Parker-Bowles, the Duchess of Cornwall's son from her first marriage, who is not officially royal at all, ended up divorced from his wife, Sara Buys, after 12 years. Sara, a journalist, shied away from the media, revealing that she suffered panic attacks from being the centre of attention on her wedding day.
It's not just in British royal marriages that commoners get cold feet. Among European royalty, there are countless examples of bust-ups. Take Princess Charlene, a former South African Olympic swimming champion, who allegedly tried to bolt from her husband, Albert II, Prince of Monaco, days before their wedding. Reports claim that she was intercepted by police at Nice airport and subsequently persuaded to return to the palace.
Meanwhile, acrobat Adans Lopez Peres divorced Princess Stephanie of Monaco in 2004, after just 12 months, and Tessy Antony de Nassau, the former soldier and former Princess Tessy of Luxembourg divorced her husband, Prince Louis, last year after 14 years, later complaining that the marriage destroyed her relationship with her family; her oldest brother no longer speaks to her. One of the most tragic royal/commoner marriages to date has been that of Princess Martha Louise of Norway, who divorced Norwegian playwright Ari Behn two years ago, only for him to take his life this Christmas.
Perhaps the uncomfortable truth is that royals scare off commoners. For an ordinary girl like Autumn Kelly, it's highly stressful to be plunged into the royal family, with its protocol and media interest. Indeed, when they first began dating in the early seventies, Mark Phillips dodged the flashbulbs by travelling in the back of Princess Anne's horse lorry.
It's telling that even Princess Diana, who, as the daughter of the 8th Earl Spencer, arguably had bluer blood than the Prince of Wales, struggled with her husband's stiff upper lip. Posing for engagement photographs with a bashful Lady Diana Spencer in 1981, he was asked: "Are you in love?" "Of course!" he said, before adding: "Whatever love means…"
While rumours circulate that Peter Phillips is distraught by the split, their joint statement insists that it is amicable. The couple's first priority will be "the continued wellbeing and upbringing of their wonderful daughters". Happily, among the divorced members of Phillips' close family, there are plenty of examples of this working out, not least his own parents, who have always maintained cordial relations, living within striking distance of each other on the Gatcombe estate.
If Autumn needs inspiration, however, she should perhaps look to Sarah, Duchess of York, who was cruelly dubbed "Fergie, the red-headed commoner" when she married Prince Andrew in 1986. Since departing the Firm, however, she has flourished, co-parenting her two daughters and co-habiting as friends with their father. "The red-headed commoner" has shown that there is life after a royal marriage.