Sometimes people dont have the gut to say the truth, and feelings are hard to express lately in a world where we all are focussed on social media which actually divides us, makes us antisocial since we all live behind our screen and basically saying everything we want...
But in the end, i believe your answer will come in the end, one time you will see him and you will have the time to talk about it.. When the time is right everything will come together!
But the bad part is that it leaves you with insecurities, what did i do wrong, where, what how when? So in youre case it really sucks since you dont really got a reason for it, so its hard for you to place... But best is to let it go, just as he let you go..
Since the more you will focus on it, the more itll bring you down.. And when you let go the answer will come your way eventually! You just have to pay attention
Take care mate, and some friends come and go, but you will find true friends once you find yourself!