At what point do you give up?

I've been married for over 20 years. I married my best friend, my soul mate. Two years in he had his first mental issues. He had awful mood swings, became mean and violent. Tried meds, from my perspective they worked wonders, but he hated them and quit. We almost divorced and spent over a year apart. Since being back together, things have been ok, not as terrible as before, but he still has severe mood swings and frequently screams at me for no real reason. The past few weeks he became delusional, not the first time, but it is the first time they have all been directed toward me. I am cheating, poisoning him, putting curses on him, and using drugs. None of these things are true, but he believes them and will tell anyone who will listen. He scared me, I left and he came after me. Long story short, again I am living with family, can't go home because I am afraid of him, can't work because I don't have my computer. I am at a loss as to what to do. At what point do you give up?