I don't care that my grandpa is dying
Then why did you use to visit or go to his place if you never cared for your grandpa?
His home is very familiar to me and I have been going there since I was a small kid, just sitting at his place makes me feel calm.
It's very insensitive to not care for your grandpa. He'll like it if you spend time with him in his last days.
My grandpa was a bastard, he disrespected my grandma when he married another woman. He has money and he doesn't share it with anyone, I don't want to be with him.
Even so, his days are numbered so I do hope that you find time to reconnect even if you don't get money from him. Relationships aren't about money.