(21F) My (24M) ex lost me and somehow still thinks hewas the victim?

My ex and I broke up about a year ago (ours was a 3 yr relationship). I'm in a new relationship and genuinely don't want him back, but today I accidentally saw a picture of him which his sister posted and my mood completely crashed.

During our relationship, I supported him through his lows, but when I needed him most, he wasn't there. He told me he wouldn't change his habits for me. I was begging him to meet me while he was apparently “busy” meeting two girls, and I only found out through his sister, who used to be my best friend.

When I eventually started dating one of my friends, he sent me abusive messages calling me a “dumb fuck”

He also seems extremely fixated on having a virgin girlfriend when he himself is not. Apparently he's with someone now who had left her previous boyfriend because he cheated, and I honestly feel bad for her. I keep thinking, what if he ends up hurting her the same way he hurt me?

And now I'm just fucking angry. I don't want him back. I don't even want anything from him. I just want to see him face consequences once. I want to see him realise what he did, regret it, and maybe finally understand that I wasn't the villain.

I know his life and choices aren't my responsibility, and I know whatever he does eventually has consequences. But why the hell do I still have this crazy rage in my head after a year?

How do you let go of the need to see someone get what they deserve?

tldr: My 24M ex and I broke up a year ago after he repeatedly wasn't there for me, refused to change hurtful habits, lied about being busy while meeting other girls, and later abused me verbally when I moved on. Now he's dating someone else, and I unexpectedly saw his picture today. I don't want him back at all, but I feel an intense anger and resentment and keep wishing he'd finally face consequences for how he treated me. I know his life isn't my responsibility, but I can't understand why I still want to see karma hit him so badly.