Why does my heart ache for him?

We're both 17, haven't talked since we were 15. We used to be good friends and we liked each other the way innocent kids do in 8th grade and freshman year. Anyways, he felt rejected and it didn't work out, now we go to different high schools. So when we see each other won't speak or smile. He literally walks away from me so I let it go. Now it's New Years and he's on vacation in Florida. which I know because he posted a pic of fireworks at the beach. He's there alone with his family, and for some reason, I felt my heart sink. Like I regret everything that went down between us because I could have been with him, in his arms you right now you know? I have a boyfriend so it's wrong to feel this way, but could someone explain why I feel so heartbroken? I never stopped thinking about him, but I've never felt this emotional the way I am right now... almost like I could cry.
Updates:
Most Helpful Guy
What Girls & Guys Said
01Related myTakes
How I understand the parable of delayed gratification in Luke
Being the perfect gentleman does women's still prefer it and does men still do it? (about 5 min read)
I have covid, but I'm almost completely symptom-free. Here's how you can stay healthy and save lives
Jennifer Lopez: Confident Humble Goddess or Braggy Self Absorbed Narcissist?
Click "Show More" for your mentions
Most Helpful Opinion(mho) Rate.
Learn more
Learn more
AI Bot Choice
Superb Opinion