I'm one of the lucky ones, I think. No matter what happens in this relationship in the future, I feel better off for having had it.
TS, you have to cut your losses. Judging by your account, she has a fully functional support system around her in the form of a loyal family, and yet she's still irrational and unable to take any ownership of her actions. If I were in your shoes she's the one person I would NOT permit around my son. If I were in your shoes I'd be trying to make it so that she'd have to ask your lawyer just to send him an email message on his birthday.