Advice please?

A little while back, I lost my virginity to this guy. We dated for 2 months and broke up. I'm normally not weird around exes, especially if we've been broken up for a while, but I just can't help being embarrassed or uncomfortable when I'm around him. I'm not sure why. I don't like him nor do I even find him attractive. I mean it's been almost 2 years since we dated and we're both currently in relationships that have lasted for over a year now. Maybe it's because he wasn't a virgin when we had sex. I also admittedly did a lot of dumb shit in the relationship because I was 15 and stupid. I was also super mentally unstable and I know that's no excuse. I just feel like I can't forgive myself. I know this post seems really unorganized and confusing but can I please have some advice on how to forgive myself for what happened/not feel so weird around him?