Our situation is different in that mom insisted that she could continue to live alone at home, but facts said otherwise. Not bathing in over a month, never changing her clothes, and eating poorly. It became gallows humor to ask how she'd been eating, because we knew that she'd always say "Oh yes, I'm eating like a horse", and yet the refrigerator remained nearly untouched. The delusions got to a point though that the writing was on the wall, where she'd be accusing everyone of ridiculous things, but to her were as absolute truths. (I suspect that things get to a point where she is unable to differentiate dreams from reality.)
Anyway, we took her, unknowing, to a home nearly a year ago, and she has no concept of how long she's been there, but keeps asking when she can go home... sigh.
Perhaps the worse of this is that she's become either hard of hearing, or has trouble comprehending what's being said, probably both. Sadly, it effectively cuts her off from being able to converse with others. I remember a blind person saying once that they were glad that they weren't deaf, for the same reasons.
