There is a piece of advice floating around lately that tells new authors, and not so new authors, NOT to read their reviews. And while I can agree to a point, notice that I just agree to a point.
The internet makes it very easy to post a lousy review, to get really nasty, to the point that they rip into new authors. It's becoming more common, and it's less likely to change.
So before you take all the advice to NOT read your reviews, think of a few things first.
What kind of person are you? Do you tend to get angry or depressed when someone criticizes you? Do you mentally yell, or actually yell when you read something you do not agree with? Would you bitch and complain, or start an internet war over a discussion you don't agree with?
If any of the above are "YES", then it may be better not to read your reviews. Why? If someone left a review claiming that your book is "worse than dogshit", you may (and I say may loosely) overreact.
However, do you tend to get upset, let it sink in then shrug it off when someone criticizes you? Do you believe that "Not everyone is going to like my book"? Do you have strong beliefs but care not to join in on an internet flaming war? Do you believe that everyone is entitled to their opinions, and opinions are like assholes, everyone has one?
If any of the above are "YES", then you should read your reviews. Why? Reviews, good and bad, play a very important part for an author. If you skip all reviews, you are doing yourself a disservice.
First and foremost: A bad review toughens up an author. Even the most well known authors, those who began writing in the age before the computer, receive bad internet reviews. This is a "thick skin" kind of business. But, then again, so are a lot of things in life.
Good criticism can, and often does, give authors something more to think of when it comes to their book and/or writing style. It may be too late to change what you've written, but you definitely can think about what they said for future projects.
Good reviews, such as "OMG, I couldn't put the book down", softens an author. Too many good reviews, with no constructive criticism can be bad, i.e. it softens an author too much. But just the right amount is a great balance when paired with similar bad, lousy reviews.
It's the age old tale: Not everyone is going to like your book. Reviewer A hated the book with a passion. Reviewer B loved it. Reviewer C gave me some good criticism to think about. A good balance.
But we're all humans. We all have feelings and beliefs, and we do get hurt emotionally. If you're reading horrible reviews and you cannot keep from feeling hurt, find someone to talk to. It's better to look outside of the internet world, and go for someone who knows your goals/dreams in real life. A friend, a partner, etc. If you have good internet friends, send them a private message. Don't let your hurt and upset feelings be known through the internet world, such as Twitter, Facebook, or a forum.
Sure, twenty + internet friends can make you feel better, but you run the risk of letting your sour feelings be known to everyone, including readers, editors, and publishers.
And do not contact the reviewer. Whether it's through Amazon, Goodreads, their personal blog/website, or another source; do not attempt to leave a rebuttal. Remember, people are entitled to their opinions. Even if that reviewer did not like your book, it doesn't mean everyone will hate it.
I hope this advice comes in handy to new authors, and seasoned authors alike. If you would like to add or refute this advice, go ahead. :)