I had a mother who was very jealous that I had a nice life. Eg Husband, child, own home and financial security.
She wasn’t insulting like your mother, but would make little snipes at me. I stopped physical visits, but kept the phone calls. Eventually I left it so she would call me (before that I dutifully rang regularly). She only ever wanted to talk about herself and all the wrongs done to her.
I did once have a very frank talk with her. But it didn’t change anything.
Remember, sometimes a person will try to put you down, so that they can feel better about themselves.
She is bitter, jealous and possibly lonely. You have a lovely life and a loving husband. It will sound crazy to you, but you have the power in this relationship. You really do.
It would be very reasonable to cut contact with her, but I understand why it can be difficult. Perhaps see this as a one/two year project. Reduce the number of times you see her. Learn to grey rock her. Learn how set boundaries with her.
”If you call me names, I will leave. Read up on toxic mothers. Try baby steps to disentangle from your mother.
You come across as a really sweet person in your post, so believe in your husband, believe in your self. Treat your mother as a joke. “You won’t believe what’s she’s said now”. You need to move her from in your head as the powerful, all knowing mother she once was in your childhood, to the irrelevant person she is now.
Best of luck