She is in denial of how far her memory fails her. She moved to be closer to me 2 years ago. She has never really adjusted and wants to move back to her hometown (assisted living would be the only way this is possible) and feels she is fine to be on her own. She also thinks she will be able to drive again. Mom would like to spend every day doing something with me but it isn't possible. I work part time and just need some downtime. I do get her out shopping, to a movie, or to my house or dinner at least 4 times a week - which she doesn't comprehend wont happen should this move back to her hometown take place. On the other hand it is ALL she can converse about and is getting very resentful and bitter that I am not making it happen. What is a professional thought. If i did move her back, I would be able to visit 4-6 weeks for several days.....
I am not a health care professional. My husband had dementia. My mother has it now. Here is what I think: You may not have the legal authority to prevent Mother from moving. But you have a moral responsibility to do everything you can to keep that from happening. For example, you can refuse to help in any way. It sounds like Mother will not be able to accomplish this on her own.
As for her resentment and bitterness, that's a big challenge. One thing you might try is appealing to her motherly instincts. "Oh Mom, I feel so terrible every time I think of you moving away. I love being able to see you several times a week. I love knowing that if I need a hug or need to talk to someone I can go over to your house. I would miss you so much if you went away, I would be devastated." Who knows? It might help. This approach was very effective with my mother.
Reasoning and explaining are probably not too helpful with someone who has dementia and is in denial. Diverting her attention, changing the subject, and moving on to an activity might be more helpful.
Can you think of things she might be able to do on the days you don't visit her? Adult day health programs can be wonderful. They usually have vans to pick clients up and return them home. If she went once or twice a week that might give she less time to brood and be resentful.
I don't see any magic wands here, but I definitely think it would be a mistake for mother to move away from you. She is going to need increasing watchfulness. She may need to go to assisted living even living close to you. Moving away will make everything multiple times harder and won't really make her happier. She'll still have dementia. :(