Sloppy Firsts, by Megan McCafferty

McCafferty, Megan (2001). Sloppy firsts. New York: Three Rivers Press. 

Summary: Jessica Darling is devastated that her best friend, Hope, moved away from Pineville, New Jersey shortly after her brother's drug overdose.  Jessica struggles with intense emotions and depression as her relationship with her family is strained, as she secretly loathes her friends at high school and chooses to sit with them in high school only to avoid being alone, and as she harbors a strong crush on an upperclassman on her track team. Her life takes a bizarre upswing when she begins a secret friendship with a "Dreg", who was friends with Hope's older brother.

Additional comments:  Jessica is an intelligent girl who wallows in her misery that her best friend is no longer in her everyday life, and she feels misunderstood and excluded by everyone else, particularly her family.  Jessica must come to terms with the way others--and herself--can be fake to others and can, thereby, be hurtful.  You might as well find a copy of the sequel, Second Helpings, because their is no real resolution at the end, only another dissatisfying problem.