Wife no longer attracted to overweight husband

How do I deal with the reality of having lost all physical attraction for my severely overweight husband? I've tried to be encouraging and understanding. I've made healthy meals for us, offered to exercise with him, and listened empathetically to his frustrations for years, but he hasn't shown interest in doing anything to change his situation. I don't think he's depressed, but all he wants to do is eat and sit around and and watch TV. It's gotten to where sexual intimacy is just a loving act of service on my part – there's no pleasure.