Heather Mills MCCARTNEY is so devastated by her separation from husband Sir Paul McCartney, she has suffered a major health relapse. The former model, 38, had an operation last month (APR06) after a metal plate in her pelvis, used to help secure her false leg, slipped out of place. And the break-up of her marriage to the former beatle has taken a serious toll on her recovery - she is spending most of her time in a wheelchair and in "floods of tears". A pal tells British newspaper the Daily Mirror, "We're very worried about her. She's at a very low ebb both emotionally and physically. "She is unable to walk and is in a wheelchair. She is in so much pain. She's in a very low place. "When you're an amputee, and in particular when you've had a revision amputation, you can be on crutches for a few days and then have to go back to a wheelchair depending on how the day goes. "She's now spending most of her time in a wheelchair so draw your own conclusions. "She's been in floods of tears and is also having problems sleeping but her friends are rallying round." The couple confirmed their split on Wednesday (17MAY06), citing "media intrusion" as the cause of their marital troubles. They met in 1999 - a year after MCCartney's first wife LINDA died from breast cancer (17APR98) - at a charity function organised by Mills, who has been an avid campaigner for anti-landmine charities after losing her leg in a motorbike accident in 1993.