Whether you apply for a job that doesn't work out, or the guy you
If you're like me and you believe that everything happens for a reason, you'd agree with Marilyn Monroe's quote "Sometimes good things fall apart so better things can fall together." If an opportunity passes you by, don't just sit there being sad for days (although definitely be kind enough to yourself yourself to take at least a day to let it all out!) - let it fuel your fire.
Do better next time. Avoid that type of person next time. Build yourself up whenever you feel down - it's the best thing you can do to make you feel better. Learn new skills that will make you a more marketable candidate, spend an extra 5 (…...or 15) minutes in the shower using a new, delicious-smelling body wash to make you feel uber-pretty, ask a new friend in one of your classes if she wants to grab lunch sometime.
Rejection can either be seen as a closed door or as an opportunity - it's up to you to decide which.
Have you felt "rejected" in some way lately? What worked best to lift your spirits?