It is important to know that the
overwhelming majority of incoming AFA classes either didn't apply for or weren't selected for SS. The purpose of SS is to experience what the it's like for applicants who are "on the fence" about attending the SA. If that describes you, it's regrettable that you won't have that opportunity this year. If you have already decided that USAFA is where you want to be, AFA Admissions just saved your parent's approx. 1K in expenses. Seriously, that amount is trivial for some, but would've been a hurdle for many. As a parent, I know families would have scrapped the money together somehow.
More importantly, now is the time to examine why you weren't selected? Some things are beyond your control. For example, you may be from a very competitive state (PA/VA for instance); it's quite possible your application would've been approved if it was from any of the other 48. Things you can control need to be reviewed in an unbiased manner. Take a critical look at your essay, better yet, have an English teacher or someone with superb writing skills review it. I'll bet it could've been tighter. Being able to communicate by writing effectively is key but especially in any application process. Like most things in life, you get better with practice.
In sports, the analogy is that "you learn more from a loss than a win." You just had an excellent "dry run" of your SA application, & it was for free! That's a good thing! Turn this negative into a positive (also a key life skill) to strengthen your SA application (your real goal anyway) by using
all of the resources available to you to get it better. You have so many when you think about it. School, librarians, internet, retired neighbor, etc. Call/email your AFA Admissions Advisor & request input on how to make your application stronger, to name a few. Form these people into a team, a team who's volunteering to help you get to where you want to be. It's all there waiting for you to use, learn, & apply. Good luck!