Dealing with haters.  Unfortunately, it's part of the job description when you run a business.  When someone takes the time to create an anonymous website, Twitter account, or Facebook page for the express purpose of trashing you, it helps to take a philosophical step back and assess the situation.  This process applies whether you are a blogger, businessperson, or online community admin/moderator.

Do I, in fact, suck?

Well, no, but sometimes a series of events happens to make life sucky for your customers/readers/members.  In that scenario, it pays to remember that the criticism is usually not directed at you personally (sometimes that's really hard to do). Better to put yourself in the customer's shoes and see the situation from there.  And you might then reach the conclusion that the situation DOES suck, which is the first step toward fixing the problem.

Is it a cry for help?

Like the person who threatens to commit suicide, you need to pay attention to the "you suck" shouter. It is simply a human means of getting focused attention.  Especially in this age of social sharing, even a random comment within an online community is easily found and spread up the chain, and the shouter knows it.

Thank you, sir, can I have some more?

Often, the best remedy is to engage the shouter and listen until they're done talking. This is tough when the person is anonymous, but the passion expressed by the "you suck" person indicates someone who cares (for better or for worse). (See Jay Baer's excellent riff on this subject here.)  I like to respond with a neutral, level-headed question, which will separate the empassioned customer, reader, or online community member from the simple troll.  (And remember, there are trolls who get their jollies from provoking you...if you find out it's a troll, back away slowly and remove the attention that's like oxygen.)  If it's a person with legitimate gripes, listen some more until you get it, and try to find the common ground to resolve the issue.

Tomorrow is another day.

And remember, you always have tomorrow to try not sucking.  Keep your sense of humor intact and move forward!