All actors have been there. It all begins with auditions. You prep until you're blue in the face, trying to memorize a monologue that shows all of your acting abilities in under a minute and memorizing music that is just right for the show. You give yourself a million pep talks, decide which character would be PERFECT for you, and walk into the audition equal parts excited and terrified.
Then, you wait. Maybe you think you killed it, maybe you think it killed you. Maybe you get a callback, and maybe you have to pretend you're a great dancer or that you can do a Russian accent. Then, you wait some more. Finally, the cast list comes out... and you're not on it.
Actors know rejection. It's a fact of the trade, and whether you're professional or a college kid trying to join the school musical, you know what I mean. But, no matter how many times you don't get that certain role, or don't get in at all, it never becomes easier. You feel like a failure. You question your own talent and ability every minute of every day until the next show comes around. You wish that you hadn't embarrassed yourself by even showing up for your audition. You watch people that "aren't as good as you" or that "you hate" get a lead or beat you out and you just want to quit. But that's theatre.
If there's one thing that I've learned from rejection, it's that sometimes, you will want to give up. And you just might. If that feels right for you, then go ahead. But... it just might drive you to be the best you can possibly be. Rejection can give you a fire in your heart that will make you belt louder and time-step faster, which just might be the difference between rejection and a role, or even ensemble and the lead. So, don't give up. Don't let a director behind a table tell you your worth. You are talented and strong, and rejection makes you an honest-to-God actor. So get out there and try.