If he shows appreciation, then maybe he feels that is showing vulnerability, and that would give you power over him, which is something he would never accept?

Some people see the world - relationships - only as win-lose, never as win-win.

It feels like, you give to him what you want for yourself. But what does he really want? Maybe he doesnt want you to give up these last good years of your health and life for him? Idk. Can you take more time for yourself?