I want to start this by saying my mother is a good mom, and I do love her. It isn't like this all the time. It just so happens that she has trouble regulating her emotions. When she's angry, if she thinks it, she says it.
I am currently a freshman in college. There was an event in the fall that involved inviting your parents to come to campus. The second day of the event, I overslept. I woke up to her calling me, and she yelled at me so loud that my roommate could hear it all despite her not being on speaker. I apologized for oversleeping, but she kept telling me how inconsiderate I was. I remember her saying "I came all this way here just to see you, and this is how you act?!" I was crying really badly by the end of the call; especially since she compared me mentioning that my roommate heard everything and tried to console me to me venting about her to my abusive ex-situationship, who used my venting as ammunition to try to keep me from telling my mom about the abuse.
She also often says pretty rude/offensive things about me being abused. She mocks me by mimicking the ways I would defend my abuser's actions in a high-pitched voice, and when I expressed surprise that she knew that they were bad, she scoffed and said that she never said anything because she was "maintaining her parent-child relationship." I know I shouldn't be upset about something like that, but it really hurts.
I was on a call with her today. I won't get into details, but I was stressed out and began to cry. She said she was worried about me, but she switched between speaking coldly and yelling at me. She told me to pull myself together, would yell at me if I didn't answer her quickly enough due to crying or hyperventilating, and it eventually culminating in her telling me she "just couldn't talk to me anymore" because "I'm not a therapist, I'm your mother." On another call today, she denied saying any of these things. She often says I misremember things, ever since I was a kid. Less importantly, if I don't have the energy to be super chipper on the phone, she gets annoyed and hangs up as soon as possible.
All this to say, what can I do? I'm just not sure I can handle the way she treats me anymore. It's so fucking painful, and this happens anytime I or her is put under any sort of stress. I've encouraged her to go to therapy, but she gets mad and accuses me of saying something's wrong with her--which is sort of rude, considering I've gone to therapy for around six years now. What should I do about this?