Honestly, as an author I have grown the hide of an alligator. But even alligators can be injured if you shoot them in the eye. I can endure agents not liking my voice. That's individual taste. Or just not caring for my genre or how I presented my story. I still get wounded when someone doesn't like my characters. They are like my children. Please don't call them ugly. Recently, I received a poor review on Wish for a Sinner. Okay, the reader still gave me an average grade. All the others have been higher. However, she hated every major character. After I cried on the shoulder of my grown journalist daughter who understands, I did go back and check this person's other reviews. Mostly, she likes paranormal romance and is cool towards other forms of the genre. So I give her credit for even trying a sports romance. It was not her thing. Arrogant athletes and the women who tame them don't stack up the same against sympathetic vampires and loving werewolves. I do feel better now.
Another that hurt was a rejection from an editor who said one of my beloved but unpublished Regencies was merely Jane Eyre rewritten. True, I have read Jane Eyre many times, one of my favorites, so it is possible some of that flavor crept into my story. I can swear, however, that Jane Eyre never had sex with Mr. Rochester prior to marriage, and just because a heroine is plain and a hero brooding does not make them Jane and Mr. R. My gal is a tart-tongued spinster who bullies a man back to health and falls in love with him of course. If you reject all arrogant masters of the manor and plain women characters, there goes half the romance genre into the waste basket. I've never sent that story out again though I do still love it. Just want to protect my ugly children.