New Best Friend (movie, 2002)

Alicia is a poor girl starting college. Hadley, Julianne and Sydney are three well-off girls in a row house. Classes begin and Alicia is paired with Hadley to work on a sociology class project. At first rejected, Alicia is finally accepted into Hadley's clique where she is introduced to a world of privilege and dangerous thrills. But her attempts to become one of them ultimately land her in the hospital.