Contact your local services for the aged..In Ohio its your local council on aging. They have a bunch of resources they can refer you to so you get the help both of you need!! Maybe a local place where he can take himself for dinner..and the company of others his age. He may eat better if its a social setting. But eventually you will need the help of others sometimes so you don't burn out, and there's nothing wrong with it. Its hard to look after our parents, and hard for them to be looked after. I wish you strength for the journey.