I Broke My Engagement for This Secret Lover

My fiancé and I have been together for five years, and we're both set to tie the knot in a few months. But there's this other guy, let’s call him Jack, that I’ve kept secret since before I even met my fiancé. We had an affair for over two years before settling into a more casual arrangement that somehow never ended, despite the engagement. The thing is, it wasn't about cheating; it was because Jack truly understands me in ways my fiancé doesn’t. One night, after another fight with my fiancé, I called Jack and told him I needed to see him right away. We didn't talk much, we just started kissing, and it felt so natural. That night, we made love like it was our first time all over again. It’s a shame that this kind of intimacy can’t exist between two people who are supposed to spend the rest of their lives together. I know what I did is wrong on paper, but honestly, if I had my choice, I’d break off with my fiancé and go back to Jack. And I wouldn't even feel bad about it.