There was an interesting article in The Guardian newspaper by Julian Baggini, about how sensitive writers are to criticism.
( some great stories on writing beneath this article, and do read the comments section )
One of the first pieces of advice that I’d give to anyone considering writing a book, is to develop a hide as thick as a rhinoceros. Everyone thinks that they’ve got a book inside them, but nobody considers what will happen when the book is released into the wild!
Being an author is setting yourself up as a target for criticism and rejection. These brickbats will come from friends, family, readers, publishers, book-sellers and critics. That’s if they say anything at all, for being completely ignored is the usual fate of a freshly published book. This is why writers welcome adverse criticism, for at least it means that someone has noticed you.