"but i am not going to let him use them to get to me bc he is upset or mad."
Your husband spending time with the kids isn't using them. He may be trying to do things to make you mad, but he can't do that unless you allow those feelings to emerge inside. That's what detachment is!!! It's not about physically detaching from your husband and avoiding him, It's about not letting what he says or does bother you. Detachment needs to be emotional. When you can do this the fighting and anger can start to diminish because only one person is angry (not you!!!).
He can't "get to you" unless you allow for those feelings. If I were you, I'd thank him for his interest in the kids and invite him to the party.
There is no arriving, ever. It is all a continual becoming.
