Songs about a girl not liking you back?

Ok I'm a guy and I've just been feeling empty inside without this girl. I've known her for about 6 years but i've started liking her since the beginning of this school year. It's already the end of this school year and I've basically given her signs that I like her (Liking every status on FaceBook. Talking to her on fb. Doing quizzes on fb that answer questions about her such as "what do you think of her" and I've always put "Cute!".) Now she just doesn't seem to really like me (she doesn't seem so enthusiastic when talking to me on facebook anymore. normally she would always say BYE ;) but now shes started to say bye... or not even say bye at all. the funny thing is that her brother used to be my best friend but after a few decisions that he's made, i dont talk to him anymore. but i just want to express my emotions by finding songs and playing them on guitar. i havent picked up my guitar in years but these emotions make me want to pick up my guitar and play it. I've never felt this way about any girl before and I'm surprised im feeling like crap. But back to music, I love Taylor Swift (lol) but I've already heard invisible and teardrops on my guitar but those songs dont relate to me cuz she doesnt like anyone right now. Is there any acoustic songs about a guy liking a girl but her not liking him back? I just want to play it and post it on Facebook and hopefully the girl I like sees this and maybe she might know its about her. I just want to let her know that I liked her. I know that she had an Idea that i liked her (thats what her best friend said) but her best friend also said she didn't know if she liked me back. Well after giving her my number and her not texting back, its safe to say she doesnt like me.