Alzheimer's is a terribly tragic disease. Glen Campbell recorded a song he co-wrote and recorded in 2014 called "I'm Not Gonna Miss You" a few years before he died due to Alzheimer's. He had already Alzheimer's for 3 or 4 years when the song came out. Listen to the words. It's heart-wrenching when you understand its meaning.
I'm still here, but yet I'm gone
I don't play guitar or sing my songs
They never defined who I am
The man that loves you 'til the end
You're the last person I will love
You're the last face I will recall
And best of all, I'm not gonna miss you
I'm not gonna miss you
I'm never gonna hold you like I did
Or say I love you to the kids
You're never gonna see it in my eyes
It's not gonna hurt me when you cry
I'm never gonna know what you go through
All the things I say or do
All the hurt and all the pain
One thing selfishly remains
I'm not gonna miss you
When you realize he's not going to miss the love of his life or his wonderful children because he won't even know who they are...
Dude.