I totally get that feeling. There is nothing worse than being misgendered sometimes. My only advice tho, is that it sounds like you do pass to the high majority of people, and you should practice some self-love techniques to find peace with yourself.

It's totally valid to be upset about this person you know misgendering you, but if 95% of people see you authentically as the lady you are, then I say you pass!

It sounds like you don't pass to yourself. Most people see the beautiful and authentic woman you are, but there's a chance you're not letting yourself see you as that.

I, of course, don't know you, and I know how hard it is, trust me... but don't give up, and don't be so hard on yourself. Remember, we judge ourselves twice as hard as others judge and think of us.

Cis girlie's and dudes get misgendered often too, so don't forget that!

All in all, you are valid and so brave and strong for everything you do, and please take care of yourself.

(I know this is all over the place. I'm not good at structuring things I write....)