WHY?

I've dated a guy 5 years ago. I was a rebound though. Pero until now, I think of him. At random time of the day. After he ghosted me and went back to his gf(ex that time, yun ang Sabi nya) he blocked me too 2024, when my mom's at the hospital, nagulat ako his name popped up and the notification says, he started following me. Pero when I checked, I was blocked. Wala, nakakaloka lang. Now, he married the girl and living at Canada. Yes, I checked. Kasi nga naaalala ko sya. I gotta stop that pero why? Why can't I can't forget him?