Help! I'm not sure what to do?

I don't have much of a social life, only a few friends or so. I am in high school and my grades are: C, C, B-, C, and C-. What's keeping me from dropping out is this girl. That's a good thing right? Well it is actually a bad thing as well. Many other girls I liked in the past I only sought for looks but did not appreciate their personality. This would be the first one for whom I'm attracted to because of the way she is. I've been infatuated with her for 4 years (a lot huh?). How do I balance between school life and social life?