People who flame other people's work, with no regard for the effort put into it, are disrespectful and immature. They are mean for no reason other than that being mean makes them feel better about their own faults.
If you receive a flame from someone, don't take it to heart. If you really put effort into your work you don't deserve it.
If it is anon then you can delete it. If it is not, protect yourself from further harrassment by blocking that user. One person to block right away, whether you have received a flame from her yet or not is Kutelizzy, and Kuterlizzy (member numbers 526002, 496002).She goes under both names and leaves cruel, unjust reviews everywhere she goes. If you view her work you will see a lot of what are basically diary entries. If you leave a review she doesn't like she will target you and leave nasty reviews on your works. Protect yourself from her potential harassment.
Good luck to all of you writers who are here to better themselves.