I know it's tough to deal with at first. But the sooner you stop looking at it this way, the better off you'll be. Casting is not about fair. It's not about who deserves the part. It's not even about who you think is "right" for the part.
What it is about, politics aside, is what the director thinks is right for his vision of what the part should be. And the big point here is that you can never, ever, ever be inside his head to know what that is. So second guessing these decisions is just an upsetting excercise in futility. For all you know, his vision for the part is the girl with really big ears because he thinks that will add humor to the part. Or maybe he thinks blue eyes are important, or he wants a more masculine girl, or has a quirkier style of singing.
Bottom line, you can't make it about you and your talent and fairness or you'll die in this business. Really practice walking away and letting it go and looking at it as one step in the process as opposed to a personal talent judgement/comparison. Immediatley go into the "what's next" mode.
You're going out there a youngster, Peggy Tinker, but you've got to come back a star!
Art has a double face, of expression and illusion.
