Well, ctack2, sometimes people who act in that strange of a way are coming down with First or Second Stage Alzheimers, and they're not really talking to you, they're talking to an alternative reality field no one else can share with them. Under the circumstances, you conducted yourself in as good a way as you could to this rudeness, which no one could have changed, except perhaps a skilled nurse. She's lucky if she made it home without making a wrong turn, hurting herself, or someone else.
Another health issue could have been she had a mini-stroke in which she could still partially function.
imho