This all sounds like attention seeking behavior. She could certainly use a consult with psychologist, but a few family sessions might be in order as well.
Just my 2 cents.
I come from a divorced home. My sister was about here age when the divorce happend.
Think this though. You are a 16 year old girl. There are tons of presures on you already. In this midst of this, your parents get a divorce, and you suddenly have a new 'dad' in the house. Even if everything has been reasonably amicable, this kid has been on a rough road.
My parent sent my sister to The Hyde School out in Maine. From what I remember it is expensive, but they take a rather brutal 'cut through the BS' approach that brings about change. My sister attended the Bath, Maine campus. It helped her, and it helped the family.
http://www.hyde.edu