There is a report button on this and every thread Jerf so you can notify the moderators if anyones posts go too far and upsets you. I think they then make a judgement on how mean the comments are and act accordingly. The button is to the left of the quote button.
I would advocate just turning the other cheek,however, all art is self exposure after all - and if it is a chilly wind of criticism that blows you should just try and gird your loins and harden your resolve and enjoy yourself.