Yes, some people cause me to shut down, freeze, lock up as do certain phrases or tones of voice that anyone might use. Hecklers used to do it to me, especially those that did disgusting things such as throwing used tampons at me (yes it happened twice to me, once off stage and once on stage. It has happened to at least one other performer that I know of, all three incidents have been for religious reasons- due to the faith of the performer but, I am not the same faith as the other artist that has endured the same treatment.)
As other have said, confidence is the way to beat that. Know your talents and focus on the things you excel at doing. Use that to power your confidence, the fake the rest until one day you realize you aren't faking it anymore - you have it and, you can rock the world in yet another area.
Believe it or not, in high school I had horrible stage fright. I got the lead as Macbeth in a play my junior year, I did fine in rehearsal but, froze as if I were a wild animal caught in that spotlight when it came time to perform before an audience. Just 18 moths after that, I was on stage, playing keyboard and, singing to a crowd over over 3000 people with 4 spotlight on the stage, one of them centered on me for my vocals. I was faking it then but, a year later, it hit me mid concert that I wasn't faking it, I felt it, I was fabulous and, I knew it - I loved it, it felt natural, easy, like I belong and all of that screaming and cheering out in the audience really was for me, what had been an act and, the cheers that I never believed were for me became real, it wasn't an act anymore. I felt it and knew they were screaming for me because the loved what I was doing and, doing it was second nature to me.
In that moment, the world became mine and, nothing beats that feeling. You can do it in everyday life too, and someday, it will hit you that you aren't faking the confidence, the self assured attitude, it will be real. Yes it is an act always but, one you learn so well that it becomes natural to do it and, then you feel the results, the feedback, the approval of other that naturally approve just because you are confident. That energy feeds your confidence and, before you know it, that piece of the world is yours to command. Then you expand on it, take it to other things, and though it takes years, one day you simply stop being afraid because you know how to be confident.
That doesn't stop things from bothering you, hurting you or, upsetting you but, it does stop you from panicking and worrying. You know you can play your confidence card and, get through anything, even if you hate it.