KaMaMom above was probably this forum’s best warrior ever when it came to picking the situation up by the bootstraps and re-adjusting while maintaining a sense of humor. I encourage you to search on her posts last year. They are inspiring.
But know that all of this potential and actual disappointment is great practice for what is to come which will feel as dramatic but will be about nonsense though so real in the moment like, “I didn’t get cast in the show and everyone else in my grade did” or, "3 out of 4 of my quad-mates want to live together and I’m the odd guy/gal out so I apparently have no friends blah blah and blah once again.
And then… magically the next year your kid will have the lead. And the roommate that they ended up with when they were rejected by the freshman quad friends will be the best man/woman at their wedding. And the show they were not cast in freed them up to do a student film which won awards and it becomes the next big thing at the Indie festival.
Kumbayah. The audition year is only the beginning of the random bunch of whatevers that are to follow.