(((((((granite)))))))
I don't think you have to go to the mother for Christmas if you don't want to. You have the right to take care of your needs first. Will your husband help support you in your decision? Maybe he can read any hateful letters you get and can tear them up so you don't have to see them.
I still wish your T would just READ what you have to say. That would get it out. My T lets me email her because she says it helps me to unload. She knows I need to do that. It helps her to know what is going on with me. I'm sorry that your T won't let you do that. I wish I could talk to her and ask her why she won't let you unburden yourself through writing the way you do here. Does she know you write on a forum?
And, yes Googley is 100% correct. You are cared about very, very much here.

