Ellipses: It was the same for me in junior high. Music was a place to redirect my energy and escape from the bullying. When I was ready to think about college prep, I had astonishing self-discipline and concentration skills from those years of music rehearsal, and it kept the math side of the brain working perfectly. I aced a physics degree, and I couldn't have done it without the musicianship skills taught by my band teacher.
You just need to get her through junior high with a minimum of damage.
If you can find a mentoring program for girls through a local college, go for it.
I'm female, and I can tell you that junior high is the age where the capable girls lose interest. There's only 10% women in electrical engineering, computer engineering and physics. It's a wonderful career for the ones who can survive the bullying in school.