<human>: Condense the text into a few key points

I am not a crazily unattractive guy. I am not overweight, I have a decent amount of muscle, fit, etc. I am kinda quiet yet I'm not shy, it's just that I often have nothing to say. There's this girl [15 F] I've liked for a while. At the beginning of the school year, I talked to her and it really, rrreeaaally seemed like she liked me. And then boom. It now seems like all the signs are gone and she doesn't like talking to me and she doesn't approach me and it's like she *dislikes* me now, totally not interested. The thing is, it's not her mood that's changed, she still acts the same in general and to other people. But to me, nah. There is no single event that changed this, it happened sporadically and I've begun noticing it after a couple of days 2 weeks ago. Fuck, I was happy and enjoying life and it all crashed down, and I just can't explain or figure out why. If there's any additional questions you have, feel free to ask. Thanks for your help.
<bot>: Girl liked me then suddenly seemed to not anymore for no clear reason, not going for the better either(a rollercoaster that only goes down).