Hi Fox and Hound,

You are a minor.. so there are a few things to consider for your therapist.
1. The Law
2. Ethics
3. Clinical Practice

This means in general your therapy is semi-confidential. As it is your parent/guardian to gives the consent to treatment they have a right to know the content of your treatment.
But it depends highly on your age. There is a difference if you are 10 years old or 15 years old. A therapist will tell you in advance how far confidentiality can go with you and you could ask that question very specifically. Ask about what she will do, in which cases she will inform your parents etc.

BUT, the therapist is first and foremost there to help YOU! They will make the judgement about what they will disclose or not. They won't disclose everything usually, except if you express suicidal thoughts very often or if your depression puts you in danger in any way, harms you or your surroundings in any way. Most therapists will keep a high level of confidentiality with adolescents.

I hope it goes well and I hope you feel able to ask your therapist all these questions.