Don't Take It Personally
This seems like an obvious one, but it’s good to remind yourself that the people that are writing nasty or negative comments probably don’t know you in real life. They have not put as much thought and effort into their words as you probably have into yours, and aren’t as invested in what they’re saying and how it might be hurting you. Most people just have a knee-jerk reaction, comment on the first thing that comes to mind and move on. Also remember that some of these people are bored, and it’s much easier for them to tear someone else down than to do something constructive themselves. So keep a cool head, your emotions in check, resist the urge to respond, and move on.