I'm going to tell my mother in-law to gtfo
What has she done to deserve this?
She always puts me down and disrespects me.
I understand why you're so upset, but your should tell your mother-in-law to gtfo because it's rude to swear at people, especially your family. I think you should calmly let her know that you don't like what she's been saying, and that you'd appreciate it if she stopped.
Why would I do that? She deserves it.
You know you still come off as really rude with that language. Maybe it would be better if you just avoided her and put some distance in between you.