:bism:
:salam:
Brother, This is a difficult situation to be in. and may الله make it easy for you. no matter how much that your mother is abusing you, you have to respect her.
1-Have a Break
First you have to take a break, because if you don't take a break you would get more angry and start to disrespect your mother, so have a break be patient because we don't want anybody to disrespect his mother.
2-Get someone to support you
Talk to your friend or anybody that is near to even if it was your brother or father to feel more relaxed.
3- Act Kind with her
This is an important part so we can solve this problem. Sometimes when your are alone with her and she talks to you try to respond to bad word with good words because it won't be easy to be mean to someone if they are nice.
and may الله give you patience.
source: https://aboutislam.net/counseling/ask-about-parenting/young-hearts-minds/deal-emotionally-abusive-mother/