There could be a cycle with your mum.
Talk nasty, get daughters attention. Daughter absorbs nasty things said , reacts to mum out of guilt. So mum does it again. And it continues.
Start with one thing and your mum is easiest as you can't see her.
Next text or phone call that is nasty your reply is.
"Stop, I will only talk to you if you speak nicely"
Go silent. Say nothing more until she reply's.
If her reply is accusing or nasty, you repeat the above sentence and then say nothing.
Repeat, repeat, repeat.
If it goes on you then say. "Ring me / text me when you only have nice things to say, goodbye".
Then put the phone down or stop answering texts.
Do it. You can do it. Be strong. It is her problem not yours. She is the wrong one. Practice it.
If you do this and keep doing this you will grow a little bit stronger and stronger. You'll become more confident and believe in yourself. Then it will start to filter out into other things. Like how you deal with your husband.
Start small to gain big things.