Can my parents see my medical records?

So apparently by law (I'm in the US), I have to give written permission for anyone to see my medical records (since I'm over 18)...but...I'm still on my parents insurance and they tend to still bring me to doctors things. I feel like they're going to end up seeing records anyway? I feel like they have been. I don't remember giving any written permission for the past two years.

Basically I'd like to actually like to get some shit done in my life despite my trappedness. I'd like to maybe see about getting tested and maybe treated for things like depression etc. (Money/insurance is also a factor but maybe I could get a crap job just to have my own insurance benefits? Idk how that stuff works but...)

I just have to be very careful because I don't want them to find out and then cause a shitstorm in my home. I'd lose privacy. I like the stable home life that I currently have and I would not like to disturb that.