I'm at the end of my rope; I remember a time when my daughter, Angela, was a sweet and kind little girl, and around the age of 9 there was a sudden snap and everything about her changed. She began to withdraw, became very quiet and solitary. I blamed it on puberty and figured that it would change as she got older. The behaviors evolved and she began mouthing off to teachers at school; I was in the school office at least every other week to talk about her behavior. Skipping classes, she's very disrespectful to me, seems to be either always sad or full of rage. Now at age 15 I've caught her drinking more recently, and she sneaks out of the house to be with friends that I think are nothing but trouble. Angela is very secretive, she put a lock on her bedroom door without my knowledge (when I found it, I had my brother help me get into the room and remove the lock), and I found a locked box (that my brother also helped me get into) containing a series of notebooks. I decided not to read these books for the time being, but I find it strange that she would lock up like this.
Was I right the first time, is this just puberty affecting her head? Or is something more serious at work here? I need ideas of what to do. I'm at a loss