Liz, a little back story.
My mother is boarderline personality-untreated (Noth'n wrong with her...) I would come home from school never knowing what I was going to experience (sometimes she would go weeks being ok) It was stressful on my brother and I to say the least. My Dad stayed with her to protect us as in those days 70's he would have had a hard time getting custody. In fact I don't even think Boarderline was "invented" yet. Anyway, he would hide under the bed with us when she was difficult and looking back she sucked the life out of him. he passed away 3 days after he turned 65 in 1996. Under different circumstances such as the era, he would have been better off had he left her. I know my brother and I would have been better off if we could have lived with him. When my mother went away for a vaca with a friend, it was fun at home. We had friends over, my Dad was more relaxed. our house was a great place to be.
I hope you find your way soon, whatever that way is. But you deserve to be happy. Please don't have a spouse suck the life out of you.