Hi Mike,
I wondered, reading your post, if there is any alternative to your living situation? Is there a relative or friend you could stay with for awhile, or try to get a place of your own?
It might be a good idea, when things are quiet, to explain to your Mom that you really find it stressful when she brings you into the drama. Hopefully she will understand. If not, I guess you can physically move to a different area of the house and put on headphones and try to relax listening to music.
I wish you well.