I might have cried ten or more years ago for not getting cast in the show (or the part) I wanted. I might have been really low because it would have felt so important, so heavy, and so monumental to me and my self-worth. As a slightly more evolved adult, my perspective on rejection has shifted. I have much bigger priorities and levels of importance in my life than one single part. I have also dealt with new types of rejection (at work, in relationships, with a child, etc) more often than I did in the 'old days.'
However, the stakes are high in a new way: in my former/single/more carefree life, there would be another chance to try again just around the corner - another audition, another show, no matter how far the commute, no matter how little I knew about the company. There were also more parts, because when I was really pursuing acting, I was so much less picky. Now, with a family and a day job that's non-negotiable due to said family, I audition so very occasionally, that you bet I pick and choose, and when I do, my heart is likely set. Mix that in with the mortality reality that comes with the graduation into true adulthood, and it seems like time is slipping away, and taking my chances with certain plays/roles/experiences with it.
So, I might not cry about being rejected, but I might not just move on, either.
Luckily, 'adulting' can also mean that I don't have to wallow in self-pity with no resources (or no lack of pride to tap into them). Knowing full well much of this is simply a perspective shift (what ain't?), I'll reject the rejection with maturity and grace (and also maybe-probably-definitely repeat 'That show's gonna suck without me' - to myself, of course).
Rejection vs. Direction: What if you had been cast in the show and it turns out that the director has a different point of view/style/attitude toward the role? Doubly concerning if it's a role you really care about. The 'dream' in 'dream role' can quickly disappear if once you get it, you can't really do it your way. Though of course because you were not cast you will not be able to prove this, you have to think that if the director did not deem you the best choice for this role, you might just have dodged a bullet in working with someone who sees things differently than you.
Rejection vs. Protection: Let's face it, when we are in a show (especially when/if/because we are also working, schooling, parenting, partnering, doing more acting/producing/educating, etc), we are going to get less sleep, eat a little more lackadaisically, and going to max out our good selves. Not being cast in a show means more time for health and wellness. How many times have you been rejected and while the giant voice of sadness and hurt is screaming, that tiny little one fights to remind you 'Isn't it great to have your nights off, though?'
Rejection vs. Connection: Especially in those instances where the part you wanted to play meant a lot to you, you felt a huge kinship with, or involved a story you truly felt you HAD to tell, releasing you from attempting to tell the story through acting will help connect you with the reason why it meant a lot to you in the first place. Say a part resonates with you because its story is strongly centered around a difficult relationship or an internal struggle, or even a political issue you are passionate about. Performing a piece about it is cathartic and personal and gives you a chance to share a story you understand intimately. But if you don't get the part, you won't get to tell that story (until there's another chance to audition, produce it yourself, etc), but you DO have the chance to devote your time and energy to the person, work, issue, or your own self instead. Be grateful the rejection will allow you to give to your original inspiration; nurture it, and bless it with your attention and love directly.
Rejection vs. Perfection: If you're like me, there's a lot of unwelcome but inevitable anxiety about performing. I struggle with wanting to be 'perfect' in a role (whatever that means), and worry endlessly about whether I'm making the director, co-actors, and eventually the audience 'happy' (whatever THAT means). While I don't think this is a single reason to never act again, a rejection means avoiding that uneasy counterpart of being cast- the 'quest for perfection' side effect of playing a part that feels like a once-in-a-lifetime chance.
Rejection vs. Reflection: It's a cliche, but it's completely real: you need to be a full, versed, experienced person to reach new levels in acting. Being onstage is why we do what we do, but it also regularly keeps us out of opportunities to learn new skills, meet new people, and do some basic life living that are key to our contribution of well-rounded, nuanced characters. Take a rejection as an opportunity to work on living so you can bring even more layers to your next audition or experience on stage.