We're in the same boat!
Your story opened an old wound I thought was buried forever with the deaths of my father and my brother. Neither of them mentioned me in their Wills - it was never about the money, but the cold dismissal as if I never existed cut deep.
It's reassuring to discover others who've endured dysfunctional families. I hardly knew my maternal or paternal grandparents except how uncomfortable presence. Strict and old-fashioned they believed children should be seen and not heard, and preferably not seen at all.
Confiding in granny or bouncing on grandad's knee is an alien concept to me!