Why is it so hard to move on when I know I was mistreated ?

Hi guys,

Been a long time reader of this sub over the last year. Found out about my partner's affair with his colleague in May last year. We had been together for over 10 years at that point and tried to reconcile.

These were mostly harrowing months : he trickled truths about the affair, blocked her only after a few months when she messaged him every time she was drunk, we went to couple counseling but he was really reluctant and thought a few sessions would suffice, etc. I tried really hard to stay and get better and he did support me, we were still very much in love and determined to make it work.

I finally broke up at the end of the year after he confessed another old infidelity and old lies, thus confirming that he had lied to my face thousands of times after confessing the affair. I moved out and we stayed in touch until I cut ties after he became aggressive and verbally violent with me because I did not trust him anymore.

I went no contact for 6 months, focusing on myself and my loved ones. I felt relieved not living in constant anxiety anymore. He offered to meet several times but I was not ready. I tried dating apps but I was not ready for that either, I also completely freaked out the first time a man flirted with me in the wild this summer.

Recently I bumped into him and his new girlfriend (affair partner, of course). That broke my heart, AGAIN. Offered to meet and we finally had a nice closure conversation, he apologized and cried a lot. From what I've understood she reached out and he jumped on the occasion to feel a little bit better. He says he's not in love yet and I'm still the woman of his life, but he wants to see where this relationship could go.

This had been a really beautiful relationship and I'm glad it could end on better terms. But it was torture to feel the intimacy and bond by spending six hours together being physically close and then return to my single life, while he enjoys the intimacy of being with her. I can't stop thinking about him and thinking about them. I can't help rationalizing every reason why their relationship won't work : he is very obviously still in love with me, we kissed so he is already unfaithful to her, he said they would fight a lot at the beginning, etc. But I'm still jealous, I feel like he replaced me.

I can't help thinking that I'll only be fully healed when I fall in love with someone else that will treat me much better. But he did treat me right until he turned out to be a cheater. And I miss him so much.

Why is it so hard to move on, over a year after the infidelity and 8 months after breaking up ?