My crush crushed me...?

There is this girl that I am truly hung up on, she is all I think about. I will call her Jane. Jane and I attend the same high school. We had a class in 8th grade together, we were acquaintances though. This year, however, things have changed. For the first time in high school, we have a class together. We had 2 last quarter, but with time progressing, we now only share 1 class together.

In the 1st quarter, everything started out wonderfully. It was going smoothly, we spoke, we caught each other staring, we laughed. She used to laugh at everything I said. Even my corniest of jokes would receive a genuine laugh, accompanied with a smile and light blush. When we conversed, both of us seemed interested. Both of us even seemed interested in each other.

The 2nd quarter has begun. Now she won't even look at me. She won't speak to me, she does not laugh anymore, she just seems quiet around me... I can't understand why. I thought everything was going great, then this hits me out of nowhere. Whenever I talk to her, her responses are short and trite. She seems annoyed by me, I feel like I'm bothering her. I tried talking to her twice last week, both times, lacking success.

She took her friendship away, she took her kindness away, and she took her presence away, All beginning last Monday.

I can't stand looking her way anymore. Both of us used to be so lively in front of the class... now both of us sit in silence. Neither of us speak much to anyone anymore. Some days she doesn't speak to anyone, other days she speaks to everyone... But me. It's truly agonizing as I sit and watch a friend drag herself further away...

I truly only wanted this girls friendship. I loved her personality, and while she is quite attractive, all I wanted was her company. Her intelligence, her sharp wit, and her personality amazed me. I truly saw a friend, a kind hearted soul who I could connect with. Her absence is haunting me... I can't understand what I did to warrant this. It is depressing, recalling all of the happiness she brought me. All of the compliments, the kind words, the chuckles... was it all fake? Was it all an act? Did I overestimate everything?

I would ask how I could win her friendship back, but she seems to want no part of me. I don't know what I can do... Please help.