I once took a class with Dr. Fred Luskin about forgiveness, based on his book Forgive for Good. He talked extensively about his relationship/feud with his MiL; longstanding, maybe 15 years. Eventually he narrowed the gap between his expectations for his MiL's behavior and the reality and was able to find harmony.
Kind of like he was not going to suddenly be the choice son in-law and his Mil was going to behave in a certain way regardless...so he rejiggered a working relationship that reflected the reality and not his disdain and disappointed expectations. Does this make any sense at all?
In short, Change your expectations from her as a mil to reflect her reality and of what she is (not) capable. I definitely could not tolerate a 45 minute rave from anyone's MiL - I would have to walk away. Geez. That's nuts.
Hang in there. It sounds like your MiL has some complicated emotions with regards to her son/your husband. Good for you for not drinking!