He needs to move on. It's one thing for DeeDee to be a douche - though she shouldn't be. But he's having a relationshpi with his girlfriend and she failed to do the right thing and stand up for him. She took her mom's side. It sounds like she's either very young or emotionally immature in defending her mom in this (I get it - I was there once too) or this is how it's always going to be. Deedee should have been grateful that he gave her these things in the first place and then made her boys take responsibilty for what htey did.
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