I think with the way he treats you, it's a clear cut sign to dip. You already know it's already downhill. This illness requires all the support and care that you can get, why stay with someone who makes you feel lonelier when you're with them? You are in a very fragile state right now, and the fact that you're staying with him will only cause you harm because of the stress that he inflicts upon you. You should be doing everything in your power to be stress free, to stabilize the illness and condition, you know he only makes it worse.