Rejection: there is no writer who has never experienced it. Actually most everyone has dealt with rejection of some kind in their lifetime.
It’s hard enough to put your writing out there. The possibility of having what you’ve produced criticized and possibly rejected is enormous, which brings with it great fear. A determined writer will push aside the fear and risk it anyway.
Any writer serious about getting published traditionally or otherwise will end up facing readers of all kinds as well as their opinions. A cruel critique can be demeaning and is unnecessary. A genuine review pointing out areas requiring improvement can be an eye-opening opportunity in spite of the pain of being rejected.
We all react differently to being rejected. It hurts, there’s no doubt about that. But it’s a necessary evil that can bring with it the inspiration to get better instead of bitter; it can increase our determination to succeed; and if we accept the good advice that can come alongside a rejection it can be a valuable learning experience.
Keep writing, keep submitting, keep improving.