The word cast is a kind of a funny word. Is it a noun or a verb? When you audition for a play you want to be cast in the show as a member of the cast, right? How many dictionary definitions are there for the word cast? Would you believe that there are more than 5? More than 10? More than 20? Check it out for yourself. http://dictionary.reference.com/browse/cast How about that? There are some pretty cool definitions for cast and some of them do actually apply to trying out for a play don't they?
For our purposes we need to start here: "Theater-Cast: (noun) the group of performers to whom parts are assigned; players. Theater-Cast: (verb) A. to select actors for (a play, motion picture, or the like). B. to allot a role to (an actor). C. to assign an actor to (a role)."
Why isn't the past tense of cast, casted? Find out! Then make a conscious effort to use the correct word.
I hope this begins to shed some light on the usage of the word for you. You should avoid talking about being casted in a play. You are either cast or you aren't cast as a member of the cast, but no one is casted because that is not the correct past tense form of the word.
What does it mean when you aren't cast? Does it mean you aren't any good? Does it mean the director doesn't like you? Why does it feel like a personal rejection when you don't get cast? How do directors make their casting decisions? Why didn't you get the part you wanted? Why do directors always cast their favorites? These are some questions that you should seriously consider before you speak them out loud. If you aren't sure how to proceed please pick up a magazine article from Dramaticts entitled Why Didn't I Get the Part. It provides some rational observations about auditions and the proper attutude actors MUST have as they audition for a play.
When was the last time you went to a football game and heard someone complain about the coach always picking his favorite to start at quarterback? Does that really make any sense at all? Would a coach seriously sacrifice winning the game by playing his favorites? My experience in athletics leads me to believe that the coach puts in the player he feels is the best for the position in the belief that doing so is the best way to get a team victory. Aren't directors judged by how good the play is and how good the acting is in a play? Would a director seriously sacrifice having a winning production by picking his favorites. That just doesn't seem logical or reasonable to me. Even if I had favorites it would not make sense to cast them over more talented actors. What about my credibility? Wouldn't that begin to suffer after a while? Wouldn't the quality of the shows begin to suffer over time?
Learn solid audition techniques and how to properly prepare for auditions. Learn to spend your time and energy on things you can control and stop worrying about things that are beyond your control. Learn to treat the audition as an opportunity to perform.