Battlefield.

Jessica Hart is a sixteen year old girl finishing her last year in high school.
She's not the best-behaved girl at school, even though she is very clever.
Jess, always finds it hard to fit in with others. Where as her sister Lilly is the complete opposite. Well-behaved hard-working and pride of the family.
When Jess finally finds someone she can be herself with, her life turns into a battlefield.

(if the description puts you off please give this story a chance because I suck at descriptions.)