jealous

Last year i had a crush on one guy. he is two years younger than me. so for 6 months i said i wasn't in love with him but sometimes i thought about him and i always wanted him to like me. but i didn't wan't a relationship with him or anything. so i know he liked me. it was written all over his face.

One day we were practising for the Christmas concert and this girl appeared. she is a pro playing piano. me and her have so much in common. so all the time we were talking. tommorow at the concert she was there when i came. i waited for him and his friends because we always use to hang out at the concerts. when he finally came he barely says "hi" to me. and then he goes to her and starts talking to her just like he use to talk to me. i felt like such an idiot. i think it would hurt less if i saw him making out with some girl from his class. maybe i am just jealous on this girl. he already added her as a friend on facebook. what do you think i should do? i don't wanna talk to him about it because i'm not good with all that "talk about your feelings" stuff. so i really need help now. tell me what should i do? or how to forget about him.....