The Insania singer - who split from the former glamour model three weeks ago - also accused her of cheating on him and never really loving him during their three-and-a-half year marriage.
Peter reportedly told her: "It's always about you. I loved you from day one but you've given me nothing back but abuse. I am a shadow of myself because of you."
Katie, 31, retaliated by accusing Peter of abandoning her and devastating the children they raise - Junior, three, 23-month-old Princess Tiaamii and Harvey, seven, who is Katie's son from a previous relationship.
The couple's impending divorce is set to become a messy affair and there is a "sea of resentment" between them.
A friend told Britain's The Sun newspaper: "It's a war. Katie wanted Pete back, but it isn't going to happen and neither is an amicable divorce.
"He's accused her of having a boyfriend and destroying two families. He believes she never loved him like he loved her.
"There is a sea of resentment between them and a gathering storm. It's going to be one of the messiest splits the celebrity world has seen."
Peter, 36, has lost over 14lbs since the split, but is now embarking on a new health and exercise regime to get healthy for the sake of his children, whom he is desperate to keep access rights to.
Katie, 31, has denied reports she is not eating properly, taking sleeping pills and drinking too much. - BANG Showbiz
