She is talking to herself while taking a shower. She is 77 and lives independently while the rest of her family lives across the country. The past few times she has visited, she has been off. She has sleep problems and personality changes. She does these “skits” whole in the bathroom talking to her audience, God and herself.
If Grandma seems a bit off, maybe it is time to see if she an urinary tract infection. Such an infection can mimic dementia. Her doctor or even an urgent care facility can run the test. The treatment would be antibiotics. It's worth checking.