Zircon, go see a lawyer and get advice on how you can separate from him. Frankly the more you tell us about him the worse he sounds. He seems to be a verbal bully who you can't talk to without him over-riding you.
Reach out for help. Are their services that you can go to? Maybe a counselling service connected to work?
You seem depressed and unable to assert yourself or see a way out. Have you spoken to your doctor? I'm sure there's a fabulous woman inside, waiting to get out once you get through the trauma of your stroke and you current circumstances.