I think back to my own childhood. My grandparents had huge numbers of grandchildren, therefore my relationship with them was almost non existent...and they lived 90 miles away from us. It was a chore to accompany my parents on periodic visits. The grandparents expressed no interest in me or my life, but would make critical remarks if they perceived something of which they disapproved. They were wrapped up in their own lives. This was the 50s and 60s, times were hard for them after WW2 .
I make an effort to display interest in my young adult GCs lives, having watched them through childhood, but I don't expect them to reciprocate. I enjoy it when they do though. To them I'm just an old woman and I live 1000 miles away. I just get on with my life, filling it with friends, hobbies and activities. My concerns about the younger generations are in the past. If this sounds sad, don't worry it isn't...its life and we all need to make the best of it.