I cut off various members of my family at various points in my life depending on where I was and where they were. Some seem to be permanent at least so far. Others have come around. I cut my mother out for some 2 years. I did a lot of work and being cut off forced her to take a better look at herself too. Now we are closer than ever in a healthy way and of all my family she has the best relationship with my son.
It isn't easy but you have to take care of you, no one else will.