I sexually abused a neighbor

When I was young, I don't remember exactly when, my brother (5 years older) molested me and shortly after a neighbor boy (my age) also did it (separately) until his parents found out and they moved away. A girl (my age) who visited her grandma across the street asked me one day after this had ended what I knew about sex and we both knew way too much and we experimented together (approx age 11, 12, and once at 15). During the early phase of this she suggested we involve another neighbor who was 3 years younger than us and I didn't want to. I knew it was supposed to be secret but I don't think I fully understood just how wrong and bad it was. Shortly after this proposal the neighbor boy and I were alone and I suggested we engage in oral sex with the whole "you'll like it if you try it" line and "here I'll do it first" and it was just the one time thankfully.
I'm not saying any of my past experiences justify or explain what I did but I wanted you to know where I got the idea for it. I didn't seem to know it was wrong and looking back I can't imagine why I didn't. I was old enough to know it was wrong. So why didn't I. Why did I do that. Things between us never got weird and he never brought it up again. He added me on facebook I think last month and I tentatively accepted though I was so uneasy thinking he would confront me. But today I got to thinking about it way too much and had to delete my facebook.
I want to apologize to him but I don't know how or if he even wants to hear it. I'll still hate myself forever but perhaps a bit less if I could at least try to apologize, maybe redeem that tiny part of myself for not being too much of a coward and avoiding it.
Amidst all this I'm in the early stages of pressing charges against the man who raped me (the police are trying to locate him to get his statement and it should have gone to the prosecutor this past weekend either way). So imagine the amount of guilt I'm feeling multiplied. I've never believed in karma, it seemed like such a stupid passive thing to believe in. But maybe it does exist. Maybe I was raped because I hurt my neighbor. I know I don't deserve forgiveness for it and now I'm thinking I don't deserve justice for myself. If I drop my case I can see it being a blow to the entire rape victim rights movement but what if my victim sees this in the newspaper and says "why should she get to feel safer and relieved? How can she say she was hurt by someone else when she hurt me? Why are her own feelings more important than mine?"
I don't know what to do and I certainly don't know how to go about doing it. I need a lot of help.