It's about a girl w./ a beautiful singing voice. The first few chapters she ran away with a guy to Tokyo, thinking that they can survive somehow. Luckily, she managed to appear in one of the live broadcast there. I forgot how, but then she went back to her hometown. Her parents forbade her to see that guy she ran away with, people in school started to gossip about what she did. One day with that guy's encouragement, she managed to sing in front of the school (unofficially) on the rooftop of her school, and then people from the school stopped talking crap about her. Instead, they ended up enjoying and admiring her beautiful singing voice. If I'm not wrong the song she sings was what she came up with by talking about her feelings in the lyrics. Those lyrics are written in a journal she kept secretly. That's how she met the guy, he saw that very journal and they started talking.

Anyways, please help me find this manga.

I'm pretty sure it's Hitoribocchi wa Samishikute. I loved reading this manga.

________________
Nulla in mundo pax sincera
"Always go too far, because that's where you'll find the truth." - Albert Camus

Yeah!! That's it! Thank you so much~!!