The Mysterious Girl singer, who announced his split from the former glamour model last week, is struggling to cope but insists the break-up is for real.
He said: "Katie and I have separated and it has been a totally devastating week for me, to say the least. I don't really want to go into any detail as it's all still so raw and I'm completely crushed.
"I would, however, like to take this opportunity to set the record straight about one thing. You may have read or heard that this is a publicity stunt, but I can assure you it's not. How anyone could think I would pretend to split up from my wife to grab headlines is beyond me. It's just sick." Katie - who is also known as Jordan - is currently in the Maldives with their two young children, Junior and Princess, but left her six-year-old son Harvey at home.
Peter, who is being comforted by family in Cyprus, is feeling heartbroken being away from his children.
He added to Britain's New! magazine: "I haven't seen much of Junior and Princess this week as they're with their mum and I miss them like mad, I really do. I desperately wanted to bring Harvey with me to Cyprus. But unfortunately he isn't allowed any time off school, so Katie's mum Amy is looking after him.
"I miss all the kids so much. I even wanted to take Harvey to Cyprus for the weekend, but I was told that Amy had to look after him." Meanwhile, Katie has spoken of her despair at the breakdown of her marriage. She wrote on her Twitter webpage: "This is such a awful time for us an i really appreciate all your mesages an support (sic).