How do i move on from this feeling?

So I am in college. Once upon a time I was in a relationship. It only lasted a couple of months and we were both drunk a lot of the times we saw each other. The person I was with was very kind, but they were emotionally vulnerable after a previous relationship. I mistreated them, lied to them, communicated badly with them, and didn't care enough about their feelings. I always cared about them but I only really did things for me so I could get what I wanted (mostly the sex we had, and the validation of having an attractive partner - basically all the wrong reasons). After a while they dumped me and found someone else, which I'm very glad about. From what I can grasp they are in a committed relationship and happy now.

Even though this happened a year ago I feel terrible about it. How do I make myself feel better? I don't want to talk to the person because I think they would be better off without fresh contact with me. I made them cry when we were together and I don't want to risk inflicting any pain on them. I am pleased that they have moved on and I don't want to put that in jeopardy.

I want to believe that I am a good person who deserves good things to happen to them, but how can I do that when I hurt someone I was meant to care about? I know everyone makes mistakes, but that thought doesn't make me feel any better about what I did.