Parents of teens tear their hair out wondering what happened to that child who cooperated at least some of the time, listened once in a while, and adjusted to the limits set some of the time. Now an attitude seems to replace that child and an alien has taken over.
The thing is, your child is the same child, but she is growing up and pushing out. She must separate from her dependency on you. She must make decisions on her own, take responsibility for herself, and navigate among her world of peers.