I stay because like BlueMoon, i too love who he is when he's sober, & i believe recovery is possible. I don't trust or fall under false hope anymore-i am at a place currently where i am ok. I can still feel sad about the past that was good, but no longer yearn for it & let it eat me up.
I've also had a lot of panic/anxiety that started in early childhood, & to be completely alone, i don't believe i could handle it. This could be out of my hands someday of course, but i won't choose it.