Elder-caregivers

The "fight" seems too terrible to get into. But if you don't someone else will. Your Grandma sounds like beginning to middle dementia... Mom was like that 3 years ago. Now doesnt know my name. You cant force the "truth" or reality, onto someone with dementia. There is a book, called the 36 hour day which will help you a lot with your feelings and interactions with grandma. When grasp of what is real slips, it is better to just say ye s and go along with whatever is perceived as real. A logical rational discussion ends up generating anger from the person with dementia, as you become a threat... After some years, I've learned to do it automatically, but it takes practice. For example, mom's shes were wet. I said "let's go find another pair of shoes." "but I don't live here." "I know you don't, but I bet we can find a pair of shoes for you." no pain. no objection to her view of reality.
So when can I go home, maybe gets a response about let's stay here just for another month for some reason.
Also make sure you HAVE POA. My POA said I needed 2 doctors' signatures. Now mom has court a appointed guardian for profit because I had not taken the legal steps necessary. You do not want that no matter what.
you also might ask your mom to come and help. When people are losing their memory, it is often difficult for them to know exactly who and what to trust.
Good luck. I remember not wanting to hurt Mom's feelings by taking over legally. BIG mistake. Unfortunately sometimes you have to to protect the one you love.