As 3legs already said, keeping the lines of communication open and taking care of yourself seem some of the best things to do. AND keeping your sense of humor.
Have you asked your husband what he thinks you could do to help him? Or if what you are already doing is enough? Too much? I would also highly reccommend couples counseling. Sometimes it really helps to have someone else there to help keep things in perspective.
Best of luck! You are in my thoughts and prayers!