I don't have many exes. I seriously did not date a lot before moving in with DH when I was 20 (he was 19). I went out with one guy in high school and one guy when I moved to KS. I knew DH in high school but we never dated then. On the other hand, my DH dated a LOT and has many, many exes (which is crazy considering he was 19 when we got together!) - one of them is the mother of his first child (born when DH was 16)
-- Anyway, an old boyfriend looked me up on facebook. He was having trouble with his wife, the girl he married within months of us breaking up. He kept sending me lots of messages and wanted to come to KS to visit me and everything. I kinda stopped answering him and it wasn't long before he wasn't on my friend list any longer. In the meantime, his mom friended me. His mom had been my pastor at one point so I accepted. She never mentioned him to me though. About 18 months later there was a friend request from him again. He had moved, was engaged and in a very different place in life. This time he wasn't talking about the past, wanting to meet up, etc. He seems genuinely happy and I am happy for him.

Now it is all very casual. He'll like my pictures or status now and then and vice versa. That is all.
-- My DH has several of his old girlfriends as facebook friends. Probably 20 at least. It doesn't bother me though, as, like I said, we've been together since we were really young and these people are all just part of our past. They don't know my husband. They knew the kid he was when he was a teenager. He is so much different now. When we were in AZ last, one of his ex girlfriends wanted to see him and meet me. She met up with us at a pet store that his parents were at with their greyhounds (they do a lot with a rescue organization so pet store visits are a pretty common thing for them, we tagged along because my kids love the greyhounds). We chatted a little and she left. No drama, no looks of lingering feelings, etc. - My husband does have my step-son's mom on facebook but he never interacts with her. He has her there as an emergency contact for my step-son more than anything. About the only person I wouldn't want him to befriend on facebook would be the girl he was engaged to right before we got together. Truly, there would be no reason why not as she is married (happily) with 3 kids and loves her life and he feels the same about his, but still...