i know exactly how you feel. parents sometimes have immense insight into their children, and honestly, the best thing you can do is just embrace it. i know it sucks because you can't control the narrative around it, but on the flip side, you have the security now to know that things will be alright!
In her mind, I’m sure she is trying to help. Idk what your relationship with her is like, but if need be, let her know if you have something to tell her, you’ll tell her on your own time - just so she knows that you know, and so that you’re establishing that boundary. Good luck on your gender journey, friend!
Eh I don’t know if this is always the best solution. I don’t have the best relationship with my mother for non political related reasons so this happening to me really would upset me. And idk what OPs relationship to their mother is like but it still can feel like an invasion of privacy.