For what it's worth, I'm with you anon. I am dealing with something similar (not as severe) with a loved one and it is hard. Stay strong as they have been for you.
20 year retired veteran, man I have (literally) never once heard complain (ever), 80+ now, poor man is becoming increasingly confused, was in ER recently. It's very hard. He looked at me and said he was proud I followed his footsteps and served my country which hit me like a damn truck as he is the eternal Father/Coach and didn't freely give out compliments so when you got one you knew he meant it. Just a good man, the mantle is falling to our generation now anons, it's on us, this is our watch, this is our country to defend or watch die. It won't fucking die on our watch.