I think as parents, we often take these things on on behalf of our kids, and often they move on before we do.
OP, you’re a class act. You raised a smart kid who is kind and a good friend. And he’s resilient. My guess is both boys will go far.
Moments like this are hard, and most lives involve more than a fee of them. The girl you like has a crush on your best friend, you get passed over for a promotion, etc. Your son has already figured out how to negotiate disappointment and move on. How awesome is that??!! He’ll do great wherever he lands!