It's called "There's a Thin Line Between Love and Hate". Here's the link to the story if you want, TPAM:
http://www.wattpad.com/story/212492 .
Basically, there's this girl named Jordan Emery and this boy named Jesse Jacobsen. For Jesse, it's been love at first sight, but for Jordan, she's hated him and found him annoying since they met. So, for three and a half years, they've been enemies and have pulled pranks on each other. But when one of their pranks goes wrong, they're sent across the country to Camp Kingston for the rest of their senior year. While they're there, Jordan finds out Jesse's eepest secret, and then it continues from there. It's really good, and sad, and a whole lot of other things.
Do you like to watch things like Criminal Minds?