Oscar Wilde said about the same thing over one hundred years ago. If all of the reviewers love your book, it sucks. A mixed bag of reviews is the surest sign that your art is hiting the mark. After all, being different things to different people is an important goal of art, is it not?
Should any two people who look at the same painting in the same museum at the same time see the same thing? I don't think so.
So never let bad reviews get you down. Unless it's unanimous, that is.