Liz is uncertain about her goals, values, loyalties, career, and friends. Sometimes she is not even certain if she is heterosexual or a lesbian. She feels bored, empty, and is terrified of being alone. She clings desperately to her friends because of her fear of abandonment. However, her clinging behavior and her oversensitivity to any sign of rejection often pushes away those friends. Liz is most likely suffering from ______ personality disorder.