About her age I too went through a period of debilitating anxiety. Some of it I think was separation anxiety, and just trying to figure out my path in life. I was in college, but had no idea what I wanted to do with my life. I was in college, but actually hated school since the first grade LOL. Go figure I continued that route for 6 years.
These are growing pains. It is good she in in therapy I too went to a therapist that specialized in anxiety disorder. For me within 3 months I saw tremendous improvement implementing coping mechanisms, and getting to the root of the anxiety. I hope that she has found a therapist that is focusing on the anxiety issues. I did try and find my way through my parents, and certainly they were concerned and worried - it was above their pay grade to fix as it is above yours - you can't fix it, only she can. My therapist's treatment has stuck with me now for 30 years, her words still ring true for ME. The root of anxiety is trying to control what you cannot, and not controlling what you CAN.
When I start feeling anxious I immediately refer back to that, and look at what the hell I am doing.
Sorry to hear that life is a struggle, it wont always be.