toxic people and sobriety

Just needed some input about how others have dealt with toxic people and family members impacting on long term sobriety. I am going on nine years sober and have worked very hard to stay there. However, I also suffer from major depressive disorder, treatment resistant disorder and have now completed over a month of transcranial magnetic stimulation. At this point I'm not sure of its benefits but can say that I'm not wimpy depressed, mostly all the **** I've stuffed deep down over the years has come out like gangbusters but in the form of increased agitation, anxiety and an unwillingness to accept others' toxic behaviors. Unfortunatley these behaviors belong to close family members and not easy to stay away from. And so, my sobriety is now being challenged in a big way. I have in the past told these toxic people that I'd have nothing to do with them if they kept it up, then it would calm down but it doesn't go away. I know I can't change them, but my conscience will not allow me to simply stay away from my elderly supertoxic mother who now has all the signs of dementia. I really don't want to give up all my years of sobriety and yet, the challenges are more than I can bear.