Unfortunately this seems to be the way the world is working. People who like what you did do not speak up. People wo do not like it complain as loud as possible. Maybe it's because complaining is more likely to lead to responses. Or because when you have a negative feeling about something you feel more urge to speak up.

I know this should not necessarily result in mean complaints, but often it does. So, what can we do against it? Simply ignore mean comments? Take care to write better comments? Or should we just shut up when we have nothing to say?