Rollercoaster of emotions

A teenage girl is a person who cannot decide how she feels from one minute to another, to begin with, a bi-polar teenage girl is a roller coaster.
She has gone from a total brat who demands things at the top of her lungs with swearing and flying china to one that gets up at 4:30 in the morning to make me a pot of coffee so that I will give her a ride to school.
The argument that we had the other day, when I told her bluntly that if she hated living with me so much that she had to treat me so badly I would be glad to arrange for her to live in a group home (before she actually killed me), seems to have gotten part of the message, at any rate. 
She has gone back to showing some affection, at certain points, and proving to me that I am not wasting my time. We have had several talks which were actually productive over the last few days, during which she revealed some of what has been going on with her that has so upset her.
She also let me know that her therapist has not jumped onto the luney-tunes band wagon with the psychiatrist that tried to force her into the all-therapy all the time lifestyle on a whim earlier this week, which relieved me greatly.
Bringing her to school in Maine was an hour out of my day and used up about $6 in gas for the round trip. I really minded, because I was so totally broke up there. Here, the school is just over a mile away and the round trip is about 15 minutes. I don't mind at all, and as long as my car holds out and she is behaving herself, I'm okay with it.
Especially if she makes me coffee, like she did today.