I get it too. My uncle, one of 3 brothers, died recently. His older brother (my dad) and his parents are all gone. When my surviving uncle got the news, he said something along the lines of “I’m alone now”. Of course, he’s not really alone; he has a wife, 2 kids and a grandchild, all of whom he’s closer to than his brother has been in recent years. But in terms of the people who knew him when he was becoming who he is today, and with whom he shared all his history-he doesn’t have that anymore. It’s a different kind of bond, but an important one to many people.