What jumped out at me was when you mentioned she was on the phone trying to get someone to drop liquor off around the corner from her house. Never done that before. It's almost like a crackhead calling the dealer.
I think from the sound of it this girl has some deep-rooted problems, and above all else is just looking to be the center of attention. Probably didn't get much as a kid and is trying to make up for lost time. That's all fine and good, but you can only lean on that crutch for so long.
As an example, my parents divorced when I was 19. My dad was what I would call a functional alcoholic. Educated (Masters in clinical social work...hah, couldn't deal with his own family problems but could counsel others on theirs), went to work every day, but always drank his 4 or 5 beers at night,(Pabst Blue Ribbon) and always had a bottle of Mohawk in the trunk. Yep, the good stuff. Along the way he started cheating on mom. I could kind of sense at 15 or 16 the happy family wasn't as it seemed. Didn't find out about the other women till later, but when I did look back, all the nights he said he was out with friends started to make sense. When he met my future wife for the first time, he told my mom I was wasting my time on her. He is entitled to his opinion, but didn't have the balls to talk to me about it. Fuck him. Now, I was angry and upset and truly saddened to learn about all this, but I realized after a brief time that I could either use it as an excuse to repeat the same mistakes, or I could use it as an example and a life lesson on what not to do as I became a husband, father, role model for my own son.
I don't know Goth girl's history, other than you alluded to some family problems in her past, and hopefully at some point in time she will be able to see those issues in a positive light.