I hear you, Incognito. My mother is in her late 80s and has dementia, so it's like the proverbial "broken record".
However, if you ask around you will see that many in our age group are dealing with older parents who have outlived their cognitive abilities. If it wasn't "the truth" it would be something else, repeated over and over again.
But I feel your pain, because I also just get sooooo tired of hearing the same thing. Her generation isn't going to quit being a JW because most are by their very nature worker bees and haven't been thinking independently for years. They are never going to see the obvious because it doesn't benefit them to do so.
But the ones that are younger who can't see it..... they are the ones I really wonder about.