My husband waters dead plants.

Now, he's always had great hope in his ability to keep green things green, but this disease has taken away his vision. He still has vision and the several eye doctors he's seen have agreed on this fact -- one was even so charming as to comment, "Your eyes are fine; it's in your head!" I can forgive the fact because he didn't know about the AD diagnosis. Truth is that it IS in his head.
Bob continues to water dead plants. At last check I counted five for sure and two likely in a vegetative state -- but not in a good way. When people come to our front door, they are greeted by dead body #1 -- a formerly beautiful small epyphitic purple orchid, now totally brown-grey and losing leaves each time I walk by.
We also have a big staghorn fern which back in the old days Bob rescued like some people would a small kitten. A neighbor had become ill and moved; her children had the house on the market and god knows what had happened to most of her plants but they'd left this big fern hanging out on the front porch. We are walkers and day after day we passed the house, for sale sign hopefully in the front yard, and observed the plant. Literally, October, November, December passed. Finally Bob' chucked his sense of other people's private property and rescued the thing. It was bedraggled then, but still hardy and barely green. Now it just hangs wearily -- AD has done what 15 degrees below 0 could not! -- sometimes even I think I can see little new fern heads hopefully peeking out. (The rumor is that the cure drug may already be in the pipeline.)
So Bob can't see. He's lost the understanding that he needs to water thoroughly. He cares for his plants now like the bishop shaking holy water at a Catholic church service. He mists, he sprays, he lets the water run down the windows where it creates lovely streaks. He is also sure I am totally wrong and he knows what he's doing.
Sometimes in pity, I water things really thoroughly when he happens to be gone for a bit. Sometimes in self protection, I throw a small dead guy away -- hoping that the memory won't kick in this time and he'll wonder... where did that special one go?
It's a perilous road. To withold water or to give it? To bury or not to bury?