That sounds just awful for you, it must be so tough. Maybe you could get your husband to see a berevement counsellor. My Mother suffered terrible berevement when her parents died and withdrew herself. Counselling really helped her come to terms with the death of her parents then she was able to tackle other problems that had occured in the meantime.
I think you going back to work will help you and give you time out from the household. But if you could get him to talk to someone outside of the situation t could do him the world of good.
I dont think you are being selfish but I would ask that you give your husband the time he needs to heal and as the other poster said maybe look into some counsiling.
also, If he is not well...just think of the way your life would be if you really had to take care of him. It sounds like he is suffering from depression and that is truely like a bad hart. If you love your husband and Im sure you do....take care of him. THings will get better again.
your husband sounds very depressed. If his doctor isn't adressing his problems, you need to find him a new doctor. Is he seeing a cardiologist? If he's just getting worse, don't sit around and wait for another heart attack. If he's not able to take charge of his health, you need to do it for him. You didn't say how old he is, or whether his brother died of a heart attack. I know how hard it is for you, with two little children, and you need time for you, but chances are if you (both of you) don't find the cause of your husbands decline in health, he won't be around to help raise your children. I'm a nurse, and i see alot of patients that have heart problems, please if he wont help himself, help him.