"best friends forever"

Just sitting here thinking about when I was a kid and having friends. I remember saying "we'll be best friends forever. Now I think back to those days and I guess I see why we're not friends anymore. Theirs honestly only one friend I think I would still be friends with if she was around. She was my friend since birth, we were born a couple weeks apart and were inseparable ever since. But then her grandma died, and everything just kind of went down hill from there. We drifted apart and then she had to move and I thought we'd still hangout, except the only time she came to the old neighborhood she was hanging out with other people who didn't like me, and she wouldn't even tell me she was coming over or come say hi. I always thought I had done something wrong, that it was my fault that we aren't friends anymore, but I don't think that's the way it happened. I think in all honesty I just remind her of how things used to be, when things were better. I know spending time with her is hard for me because I remember Nana and I get sad, She was the grandmother I didn't have because my grandma was my mom, and then when she died I lost part of my family. I lost people that I thought would always consider me family, but now I know the only reason they were family was because of Nana and without Nana they're nothing to me. How do I let people into my life when everyone leaves....