Have you ever been in a one-sided love?

When i was younger i used to have many crushes, but then i fall in love with this one guy. I loved him since i was 12 ,now i am 17. After him i couldn't fall in love again. I just remember him over and over again. No, i never confessed my feeling cause he probably doesn't like me back. Currently he went abroad but he will return back after 7 month. And the sad part is i can't help but wait for him. I just remeber his smile, the way he talked , the way he walked, everything about him. And seeing him in my dreams never helped but make me miss him more. And yet againi know that he will never see me the way i see him.