I'm going to cut off all contact with my mother.
Why would you cut off all contact with your mother?
She's miserable after her divorce and it's too much for me to take.
You shouldn't cut off your mother. Why don't you ask how you can support her instead of ignoring her? This might help her feel better and strengthen your relationship.
I can't deal with her emotions, they're too much and there's not much that I can do.
Your mother is really struggling and may need your help. She's been there for you throughout your life and now is your time to be there for her. Just because it's difficult for you doesn't mean that you should abandon her.