I have same experience. My grandma is 78, and she has dementia for 3 years. She lives by herself in her daily life. She was diagnosed in the winter three years ago; the diseases have advanced quickly. My grandma has lost the ability to feel cold and she can’t remember what she had done in the previous day!
I have three sisters, we take turns in having our grandma living with us after she agree to, if not we take turns in going to her home every night to give her meds and food.
Sometimes, we would take her to the park, bask in the sun, and talk to her about the old days, such as the good times when she took care of us when we were little, or some of the things our grandpa loved to eat. In addition, we have sent her a dog to accompany her. Since then, she was self-sufficient enough to be on her own. This was an almost magical since she was getting lively and talkative.
So, accompanying and chatting is very useful, which all can distract them, Let them not fall into their own world. Good luck.