I've been where you are now. I too thought I couldn't leave. I was forced to leave by circumstances and it was the best thing that could have happened to me or I may still be on the merry-go-round.
I'm not going to tell you that this is unhealthy and you should pack a bag and leave now.. even though every fibre in my body is screaming go, run, don't look back. Having been in the position, I know you need to reach your rock bottom to effect change and may not have reached there yet.
All I would say is this.. keep coming back here, attend al-anon if/where possible, put things in place which help you keep as much of your sanity as possible.