...

"...He tells me that if something ever happened between him and his girl, that I will be the first one he comes too but not to wait on him."

He was kind enough to give you your answer. Trust him. He's serious. And he's taken.

It takes some discipline to train yourself not to pine over someone you can't have. Maybe taking a good long break from seeing him is in order, if you can arrange that? It could do wonders for you in the way of helping you to move on.

..

Not really. People want what they can't have, it seems like women especially. You're going to learn from this, eventually... But it doesn't sound like us telling you what's going to happen is going to have an effect... People do what they want to do and that's the long and short of it.

There's no way to prepare for heartbreak other than to have experienced it. The more it happens, the more you know, the more prepared you are.

Quite honestly it sounds like you have more issues at work than simply wanting an unavailable man... you might want to think on them.

Like misguided artists who believe that "suffering for it" makes their art... Art. LOL Then the art critics come along and humiliate them right out of that poppycock... at least the good ones, the ones that last to go on and eventually become good artists... well so goes it with some young love, I think? Youth is so full of self while not knowing self that it requires a couple of heartbreaks to make it possible to sort the real from the fantasy. And there simply isn't any way to prepare for that, nor would you want to once you've sorted yourself out.