How do you deal with being told "rejection is redirection" when you have been rejected from pursuing a career in your interest?

My dream was to join the military or get a job in defense, but it just isn't possible. I got disqualified from the military at MEPS for autism, and my waiver got denied. I can't get a job in defense. My interest since childhood has been in this, and I don't know how to accept I can't have a career in it. I don't want to keep this as a hobby either knowing I am not welcome in this field.