Having a bit of a crisis of confidence here.
Have Aunts and Uncles and cousins I have only met once due to complicated family situation (not related to a conflict). Everyone has always known we all existed.
Have no other cousins and don’t know who some of my grandparents are.
My mother is friends on FB with one of my cousins and she encouraged me to add her. So I sent a request and we have messaged over a few weeks, all quite friendly but she hasn’t accepted my request and now I feel like a bit of an idiot for sending it, after all she is a virtual stranger and we just share a grandparent. I’ve just never had a cousin
and I didn’t know the grandparent very well either. We do actually have quite a lot in common and were (unknowingly) at the same event a few weeks back - but it’s clear she doesn’t really want to have a relationship with me 
Do I cancel the request or just leave it and feel a bit crap about it.