My grandpa visiting

Today, my grandfather visited me once again. He was talking about need to do more things together and how we haven't had much time for each other during 18 years of my life (actually I met him for the first time when I was eleven, when I wanted to get to know him, being told to find him in the phonebook - perhaps a bit weird, but interpersonal relationships tend to be complicated and no need to solve it anymore, it's just deep dark past...) .
He's coming from time to time, with the same request - to do something together. We always do something and then there's always a long period of nothing... The fault may be on both sides.
My "problem" is that I don't feel very attracted by that what we should make together. It may be both by the stuff he dedicates himself to (e.g. I feel much more in common with my grandma) and also by his style of expression (he tends to speak in looooooong monologues).
But as he often reminds me, one day, he won't be there anymore and I may be willing to learn from his wisdom (and there's a lot of it). But nowadays I don't really feel that way (or at least, not most of time - it's fine to talk to him once in a while, but for me it's just enough).
Maybe I'll never miss him (thinking about how inconsiderate I sometimes am - especially now, when I'm reading the post once again...), maybe I should find my way to him and maybe I should do something with him just because of that he's my grandpa.
Why everything is so difficult??? As I know myself, I'll let my feelings decide - as always, when it's important; and I may regret it later (as it's happened many times before).
And thanks to Cherry for inspiring me to think.