I feel so much for you and your sitch, my heart goes out to you. I really believe that you have gotten some very good advice from the others on here and maybe you need to step back from the sitch and evaluate your next step. IMHO, counseling for you, at the very least, is essential and it would be a plus if H would attend as well.
The decision on whether you want to save this M is ultimately up to you...something that SNS said really resonates here....only you will know when you've had enough. You say that you do not want a D and I applaud you tenacity in maintaining that resolve. That says so much about YOU....you believe in your committment and the value of a strong, loving relationship.
The fact is, right now, probably neither one of you precisely knows what you want. This revelation has both of you reeling....he has so many issues that he must deal with right now and so do you. Yes, there is hope for you sitch, there is hope for any sitch...it just depends upon how much YOU can accept and how much HE is willing to deal with.
Again, I don't know if I am any help here, but I know that you will receive a wealth of information here that will be useful. Please know that you are in my thoughts and prayers.
"Achieve success, but without vanity; Achieve success, but without aggression; Achieve success, but without gain; Achieve success, but without force." Lao Tzu