You Didn't Get the Part

You didn't get the part. You did your best but you didn't get it. Despite that fact that you memorized your monologue and got everything down you didn't get it. It sucks, believe me I know. It's not fun and you feel like ripping your head shot to shreds. Don't!
It is alright to be disappointed. You worked really hard but this time it just didn't work out. Don't get down on yourself. It's hard not to take rejection personally. But you have to try your best no to. Directors make their decisions for a reason. Will those reasons be clear to you at this time? No. Will they ever? Possibly not, most likely they will but, it's not been unheard of.
Don't go pointing fingers, either. Just because you didn't get the part doesn't mean that the director "picks favorites" or that the person who did get it "isn't even talented". It's easy to be mean but it's not the right way to go. It's okay to voice your frustration to a close friend or family member but don't go blabbing to the entire cast how terrible the show is going to be because you're not Susie Q.
If you want to stay in the business then you can't expect to always get the lead. You will have to take the back seat sometimes. The important thing is that you keep going. If not this role then their will be another one. Even if it is your dream to play Eliza Doolittle there will be another production of My Fair Lady somewhere. Just not here and now.
It doesn't hurt to be honest with yourself either. I'm not saying throw your whole audition into the waste basket just analyze it a little. (Note: I said analyze not dissect). Did I really hit all those notes to the best of my ability? Was it possible that the last line of your monologue could have been interpreted differently?  Just think. If you think that your audition was fine then do not sweat it. There will be another role for you. And just remember. You are not alone. Plenty of people tried out for the role and didn't get it. It is not the end of the world or your career. Pick yourself up and enjoy the show or concentrate on the new audition.