While I understand the feelings quite well, don't be hard on yourself. You are not an empty shell. You are a wonderful wife and mother who has done everything right to try to save her M.
Your H is just a messed up fool. He seems too deep in his dense fog to understand the magnitude of the loss he's facing. He's so much like Sue's H right now -- but your H doesn't quite have the "excuse" of alcohol abuse (from what you've told us), whereas Sue's H definitely has that problem on top of all his other issues.
It's time you let him sink or swim.
You will get through this -- of that I am certain, because you have such a great heart and great innate wisdom. Give it over to God; lay your burdens at the foot of the cross. Focus on what is best for you and your DD's, and let the Lord take care of the rest, in His way.