My mom wasn't combative, but was critical all my life until she was in her 80's and needed me to take care of her. In her latter years, I could do no wrong. It was a strange, but very welcome change. I am grateful that we "ended" on a peaceful and loving note. In reflection I can see how insecure she was, and how she resented my independence and self-assurance.
I would advise avoiding your mother's confrontations. Just hang up if she gets abusive. Ignore her if she says ugly things in front of others. Leave her out of any and all plans, trips, & events that you can. "Divorce" her, at least temporarily. Eventually she will get the message.