Not exactly the best kind of guy to give advice in this regard but really since it's so hard for us to have these connections, be it romantic or otherwise, we may overvalue them. I'm not saying what you had may not be special, but if there's nothing you can do about it then best is to move on. By that I mean find something you like and immerse yourself in it outside your usual routine of study or work. Books, music, video games, walking, cycling anything as long as it's not a bad habit. I also found myself in a similar situation. Same thing, we hang out for while only to find out that she likes someone else, even though we hang out for weeks. Right now, I'm just trying to do stuff that I like and it's really helping me restore my self worth.