My whole life I've felt forgotten and left out. It's the one indelible feeling from my childhood. Like people enjoy if I'm there, but if I'm not, then that's just fine too.
I use to go visit my parents when both of my brothers and their families would be home. Multiple times everyone but me would be sitting together in one room talking, or whatever. At some point, after an hour or so, someone would say, "hey where's XXXX?" After someone searched for me they'd report where I was, and everyone would just go on. I was always the forgotten, ignored child. And not much in life has worked against this. Although people generally think well of me, and I'm successful professionally, I'm always an afterthought.