Hello, I'd like to help you with your question.
It sounds like your mother is emotionally abusive. And when someone is abusive, they tend to see everything as someone else's fault. You do not deserve being treated this way by your mother, particularly with the stress
you are under with your anxiety and depression. To attack your most vulnerable issues is being directly cruel and vindictive.
When dealing with someone abusive, it is often very hard to reason with them. They do not feel they are at fault. So trying to talk to them or get them to understand they are hurting you is difficult, if not impossible. So the only control you do have is how you react to the abuse.
To deal with her abuse, you can consider a few different options:
One way is to restrict your mother's access to you. Do not see her more than you need to. Don't answer when she calls except when you feel up to dealing with her. Then make the conversations short and to the point. If she tries to say anything personal, tell her that you need to go and hang up.
Another option is to consider how you communicate with her. One of the best ways to respond to her abuse is with "I'm sorry you feel that way". That does not stop the comments from hurting you, but it does give her very little to respond to if that is all you say. People who are abusive like when you get upset because they know they are getting to you. By staying neutral in your response, you prevent your mother from getting what she wants.
You can also stop seeing her altogether. Many people feel that they have to talk to their parents just because they are their biological father and mother. But in no way are you obligated to continue being abused just because she is your mother. If she was anyone else, you would run the other direction. Just being your mother does not give her the right to abuse you. If you feel you need to, end the relationship, particularly for the sake of your children who do not need to be exposed to her behavior.
To help you work through this, it can help to learn more about abuse. Here are some resources to help you:
Toxic parents by Susan Forward
Adult Children of Abusive Parents by Steven Farmer
I hope this has helped you,