In cases like this one of the most difficult issues is considering the whole picture. It sounds like this young lady is dsythymic, has major clinical depression, and has borderline and perhaps histrionic personality traits. At base level is a person who has virtually no relationship with self and is buffeted around by opions of others/media;/culture. Of course she is lost. This is a hard age as it is let alone to suffer this much. Start asking her to think about her relationhip with herself. There is likely much self loathing and intense need to be perfect. Self abuse is a way not to feel self-hatred. Have her think about what she thinks she is being told by the world she is worth. Emotions change slower than thoughts validate falling back but keeping moving forward until she starts to automatically discuss with self issues of her own self worth. You will have to be hopeful for her as well as keep her in the here and now while helping her understand how the then and there impacts here and now. Take a look at defensive functioning scale in DSM IV. Look at apathetic withdrawal and acting out then take a look at self-observation, affiliation, anticipation. Note the levels of functioning. This is the space you need to cover. She will cover it best by beginning to listen to her own talk about her own self worth and a good deal of psycho-ed around structure of ego and validation around normal difficulties that people experience.