Guilt

Okay, so let me begin this with that you should only feel guilty if you really deserve to!
Gene deserves to feel guilty. He deserves to have his conscience eat away at him and he deserves to have to live with the fact that he permanently hurt his best friend. But really, who decides if we should really feel guilty or not? Sometimes, I think that people convince us over and over again that we are at fault so we just believe we are guilty. And half of the time, we really aren't.
And yes, Gene did push Finny, but those kids in the basement had no reason to harass him. It probably just added to his guilt even more.
The guilt is very obvious though. If he didn't feel bad about it, then why would he flashback and tell the story? I think he's trying to tell us that we can move on from the past.. but that doesn't mean that we accept it and forget it. There's just somethings in life that you have to live with and take into the future with you. And deep down, you know if you were right or wrong, so don't let other people get to you.
Gene moved on from the past, but he still vividly remembers what happened that summer. Just like if you went through an accident, illness or anything else dramatic, you're going to get better and move on, but that's going to stay with you the rest of your life. So just make the best out of it and don't dwell on what could have been or how you could have prevented it.
I think what the author is trying to get across is that, if you regret something that happened in your past, just try and move on. And even, if you can, find something positive out of it. Because I'm sure nine times out of ten, there's at least one positive thing that can come from a mistake.

alrightyy, night babes :)