This is why Sarah has instituted a mandatory, once-a-week "Kevin, quit working, turn of the computer, and go OUTSIDE" day. Because, yeah, if you let this sort of thing get to you on a regular basis, you need to get out more.
Whenever I get insulted by a low-life jerk, I'd insult them back gentlemen-like, and block them so they can't insult me back. Final answer? ... They can't hurt me if I hurt them back. They jelly.