Prince Charles and Camilla Parker Bowles are increasingly living separate lives, amid reports the couple's three-decade-long relationship is heading for the rocks following a series of blazing rows in front of staff. As the couple marked their third wedding anniversary last week, friends have revealed that Charles and Camilla are constantly at each other's throats, as they struggle to make their marriage work. The Duchess of Cornwall was noticeably absent when Charles accompanied Prince William and Kate Middleton on a skiing trip to the royals' favourite ski resort in the Swiss Alps during the last week of March. Sources have told the UK's Mail On Sunday newspaper that the situation has become so tenuous that even the presence of Palace staff is not enough to cool down the couple's bitter fighting. "The rows have been escalating over the past three months," a Palace source told the paper. "The staff is getting tired of it, because you can't help but hear the shouting ... as you can imagine, it's hugely embarrassing when that happens." As tension between the two continues to grow, Camilla has been spending an increasing amount of time at her old family home, Ray Mill, 165km from the couple's Clarence House residence, often flying in at a moment's notice by helicopter. "She is happy to spend time at Ray Mill," a close friend told the paper. "Charles will never go down there to comfort her. He just sits it out." Sources say the couple's relationship has been on shaky ground for months, after Camilla was forced to pull out of attending Princess Diana's memorial at the Guards Chapel last August. Left shocked and humiliated by the public backlash that accompanied her invitation to the anniversary service, Camilla told friends she felt abandoned by an unsympathetic Charles. While Camilla had always felt uneasy about attending the service, she was pushed into accepting the invitation by her husband.