Just wondering....
Mom has only me to talk to and I'm also getting tired of the same topics repeated ad nauseam and the need to simplify everything...mom doesn't like talking on the phone to relatives or any hobbies/puzzles or even watching movies - her comprehension powers are fading, I guess...so is there any way to preserve whatever cognitive skills she has????
What has her doctor said about what type of dementia and any medication that could slow the progression?
Have you checked into the senior activities center aka adult day care to give you a break and her a more diverse environment? I wouldn't let her make the choice, she needs to go for your wellbeing.