Twinmom, I just wanted to let you know that you shouldn't be feeling like another fix for him as I believe that at some point your H believed in your relationship otherwise he wouldn't have married you. He probably believed that you could help him change, but as KLM and Job have stated you DIDN'T break him. Only him can sort himself out, unfortunately to me it does that he is not putting much effort into improving himself.
Yes he is good father and helps out maybe because out of guilt or if he doesn't help and you kick him out where would he go?
As for your feeling you have been betrayed and the trust is gone. At the moment it might be that you are in a protective mode as you don't want to get hurt again. I have not much experience, but what is your inner voice/ gut feeling is telling you? From all the posts you have written, you have your head well screwed on and I think that deep down you know what is right for you but are holding back because of fear. Raising 5 kids on your own would certainly be hard, and with your daughter's condition you might be entitled to have someone to help you.
At the moment I feel you need to nurture you and heal you. Maybe in time your feelings will come back but as we have all been told here actions speak louder than words if he really want to work on your marriage and better himself.