She watches every things everyone does and listens to everything any one talks about and has to know everything and expects us to answer here for every thing. it makes me feel like she is treating my like a child and I want to tell her to mind her own business but I know that is not respectful. but it is worse that having a 2 yr old around always asking shy. It's driving us kids crazy. How do we deal with 800 questions a day?
That being said, I do not believe that it is disrespectful to tell someone, (who is butting into stuff that is not their business) that "This does not concern you, and I don't intend to talk about it." It took me a long while to learn to say that, and it didn't go over well the first dozen or so times. In actuality it is your mother who is being disrespectful of your private conversations and concerns. And no matter the cause, you don't have to allow it, so you don't have to answer.
Or is she experiencing paranoia? That can be common in people with dementia. They might think everyone is talking about them behind their back, or plotting to "get" them somehow.
If she's not agitated when she's asking these questions, maybe she's just bored. Redirection might work, or giving her something to do, like folding towels or polishing silverware.
You're right; it can be very trying to be asked the same question over and over. My MIL asks me every time I see her if I've had my car repainted. I've never had a car repainted in my life. I own a classic Mercedes-Benz that I keep in top-notch shape, but MIL seems to think it looks so good because it was repainted. It's a small thing, my it drives me nuts because she asks me every. d*mn. time.