How do you react to someone who's kind of talking out of their head for reasons they have no control over?

Toward the end of her life my mom had dementia. They had her on some powerful drugs too. She’d do things like talk to her legs, or talk about her legs, as though they were separate people. She’d pat her leg and ask if it wanted a cup of coffee, things like that. Rick and I would look at each other with faint grins. Well, either you have to find some humor in it, or burst into tears.
My sister, on the other hand, would try to “correct” her behavior. “That’s your LEG mom. NOT another person! Stop talking to your LEG.” That just confused and worried Mom, of course.

Today the grown daughter of an old neighbor of ours had some pretty significant surgery, and appears to be having some complications. Lets call her Kris. She’s out of surgery and awake, and trying to post on fb.

She posted: “Hill out ok m ok….km hungry for some food”

Her Mom, who’s about 500 miles away, and couldn’t come for some reason, said, “You’re not okay Kris. You can’t talk, you are still having problems with stridor and eating and what you just said makes no sense.”

I posted: “Hi Kris! From experience I know that you might have no recollection of posting that you’re hungry, but I’m glad you did. Hang in there girl!”

Her Mom posted “She called me earlier this morning. I don’t know why because she can’t talk. All I heard was a bunch of grunting sounds. I told her to hang up and text me. She hung up and never heard from her. My guess is she went to sleep.”

I just want to kick her! I posted that the meds were going to cause her to be a little goofy for a while. I wanted to ad, “SO BACK OFF!!” But I didn’t.

Why do people do that? Do they think they’re going to change them?