I think that it's better if you tell her that you want it confidential, because letting your parents know might make them feel worse, which might also lead to more pressure on your shoulders. I too wanna encourage you to talk about it because the more you talk to people about what you're going through, the more feedback you'll get regarding your problem and you'll know how to overcome it.
We're all always here for you.. If you want a friend or just someone to talk to, feel free to talk to me.