My best advice beyond continuing to work with a therapist and moving out, is to read The Dance of Anger by Harriet Lerner. As Crankin said, you need to draw and enforce strict boundaries with your mother. This book illustrates some strategies for how to do that and also helps anticipate the other person's reactions to that boundary setting. One typically doesn't learn how to do this overnight so work with your therapist on how to practice the strategies discussed in the book.
Good luck. I'm sorry you're having to deal with this.
Live with intention. Walk to the edge. Listen hard. Practice wellness. Play with abandon. Laugh. Choose with no regret. Continue to learn. Appreciate your friends. Do what you love. Live as if this is all there is.
--Mary Anne Radmacher