Rejection is a part of life. As a child it begins when the child at school no longer wants to play with you, they find someone else and, suddenly, they are 'their' friend so you're left to watch them play without you. As you grow the rejection changes, it's that man (or woman) who doesn't want to be your boyfriend (or girlfriend), it's the potential employer who doesn't want to hire you or the mother's at the school gate who don't want to talk to you or the credit card company who don't want to let you have one of their cards (please don't send me spam).
Writers forget that publishing is a business. When they are told 'no thanks' when they themselves are not being rejected, their work isn't wanted. A few months ago I was unfortunate to read a blog in which the writer of a novel had requested a review of her book but she disagreed with the review to such an extent that she was writing profanities towards the reviewer on his blog (which shall remain nameless). Life is full of people who say 'no thanks.' Yes, it is painful but what differentiates a writer from someone who wants to be is how they overcome this. I don't mind rejection, as long as I can use it to improve. Yes, it is painful and yes, I do sulk for a few days but I will look at it, dissect it and use it to see where I have gone wrong. If my work doesn't 'sparkle enough' then I will look at it and try to work out why. I don't give in, nor do I email the agent back to tell them to 'f*** off.' Writing and getting a book published is a business. You wouldn't expect a major company to reply to you in this manner so why do some people think that this is acceptable to speak to reviewers or agents in this way? No one wants to work with a diva and agents talk.