You said, "Any suggestions on how to deal with anger and rage in healthy ways? I cannot express it to HIM: he won't validate my feelings." Of course he won't; that's why you have called it quits. He has never validated your feelings. He isn't going to start now, so don't seek that kind of validation from him.

It is really important that you truly separate from him. Limit your interactions to as little as possible. Get a lawyer and let the lawyer handle anything technical to do with your belongings, divorce, etc. (I'm assuming that is back on the table now.) There is just no reason for continued constant interaction with him. Each interaction is triggering for your anger AND it opens you up to further manipulation which has been difficult for you to steer clear of on your own.

I remember once my sister decided to divorce her husband of 17 years, she never spoke to the man again. Child custody, settlement of possessions, etc. was handled through the divorce attorneys, and she was free of the triggers of personal interactions. It gave her the personal space to deal with what was already rather traumatic and overwhelming without be further traumatized and overwhelmed by constantly having to deal with him personally.

It's going to take a clean break. There really isn't anything nearly as pressing as child custody or anything like that to warrant the constant interactions between you. Set your boundaries for YOUR mental and emotional health.