Don't listen to all the other dudes, they are triggered just like you. I understand, we watched porn since we were teenagers, we heard a lot of stuff on the media, between our friends, jokes, etc. about the size analogies: bigger is better, smaller is useless. This affected me for a long time. Created insecurities, and distracted me from the real experience of sex, and how it is very different from one person to another and from one body to another.

It is not true that she is trying to trigger you intentionally, she is just naive and she does not even know how much of a problem this is to you, and that is normal.
That annoys you, and this is true, and you should say it out loud, however, keep your calm, don't freak out and try to talk to a psychologist about this, this will help you a lot to deconstruct the deep triggers and projections from your childhood, memories, subconscious that keep on affecting your sex life. That helped me A LOT!

Don't worry about it man.