Something that's helped me (is helping me) move on from this is to look at the flip side. There are many friends and family members I let drift away, sometimes for no real reason, sometimes because it felt like more trouble than it was worth to keep them in my life. Some I ran from out of self protection.
I think about whether or not I want these people back in my life...and often I don't. I've moved on, I don't have "room" for them, I don't want to go through the bother of giving them a second, third or 600th chance, whatever.
When it seemed like everybody got a facebook page, I looked up a bunch of old friends. I was in a lonely place in my life and wanted to reconnect, I felt pretty bad and rejected that there wasn't much of a response from some of them, I was in a very needy place in my life. But now I have a little more perspective.
I was super needy and insecure, but they weren't. They didn't have a huge gaping hole in their lives that they were desperate to fill with someone.
Looking back over the years I can see many times I've done the same thing, not out of malice, revenge or anything. I just was busy with my own life and didn't make an effort to reconnect. Maybe those people were going through something and could have really used my friendship, but I just didn't see it, or didn't want to fill that role at the time.