EXCLUSIVE: Charlie Sheen unleashed a vile attack Monday morning on ex-wife Denise Richards, the mother of his two daughters and one of his last defenders, calling the actress a "traitor and loser whore" and "dog thief" on his uber-popular Twitter feed. Now, sources very close to the former couple reveal what's really fueling Charlie's newfound hatred of Denise.

"Denise didn't steal the dogs, he gave them back to her," a close friend of Charlie's tells me, referring to two pugs that no longer stay with the actor. "They were in horrendous shape. He doesn't want the dogs, he wants to fight!"