F20/M22, dated 1.5 years — Two years after our breakup I still can’t stop thinking about him. How do I move on?

I really need advice because I’m going in circles with my feelings.

I dated a guy — let’s call him A (M22) — for a year and a half, and I was absolutely in love with him. We broke up in 2022 because he thought he didn’t love me anymore. But even after the breakup, for almost two years I couldn’t stop thinking about him.

At the beginning of this year — so, two years after our breakup — we reconnected. I was happy at first, especially because he told me he had also thought a lot about me. We’re very “in sync”: we often think of each other at the same time, sometimes even messaging simultaneously.

But when we started talking again, I realized I wasn’t fully invested. I didn’t feel much desire to sleep with him, sometimes I wasn’t mentally present, and I convinced myself I didn’t love him anymore. Meanwhile, he had changed many of his old flaws, and he was basically the perfect partner — yet I couldn’t respond the way I expected. Eventually, we stopped talking again.

Now that we’ve cut contact, I can’t stop thinking about him. It doesn’t feel like my other exes — with them, I don’t feel this constant longing. With A, it’s overwhelming. At first I thought it was just confirmation bias, but it feels deeper than that.

The issue is, I don’t want to reopen old wounds for either of us by reaching out again, especially if I end up confused.

So my question is: how do I move on from this and stop obsessing over him? Are there practical steps I can take to finally let go?

TL;DR: I dated a guy (A, M22) for 1.5 years and was deeply in love, but we broke up in 2022. For almost two years I couldn’t stop thinking about him. We reconnected at the beginning of this year, but I wasn’t fully invested and eventually we stopped talking again. Now I can’t stop thinking about him — how do I move on and stop obsessing over him?