I've had bad experiences on forums at times, and I've also had bad experiences with being talked about on forums at times, and I've tried to learn that if I'm not actually doing anything wrong then it's not really my problem. In my case there's a small but vocal group of people who think they know what goes on in my life and in my head better than I do, and have made an enormous fuss about it attributing assorted outlandish motivations to me, but in the end they don't know me. I do, and my friends and family do, and they end up being the ones who matter. I could spend a lot of time trying to correct the bizarre ideas that people have come up with, but I have more important things to do with my time and energy for the most part. The people who really hate me and insist on misinterpreting and misrepresenting me (as opposed to people who genuinely disagree with me or I've done things to p*ss them off or we just don't get along well) have their own problems far worse than I do.
I was recently at a conference where a guy did a particular exercise with us on dealing with bullying, that basically took this approach too. He said that "just ignore it" isn't a useful strategy cognitively. It doesn't make sense. People can't ignore these things. But he said the trick is to put it in context. If you're not doing anything wrong, and someone else is being a jerk, then the problem is that they are being a jerk, and that shouldn't be your problem. He talked about learning to repeat in your head, "I'm okay, you're mean" to drown out the messages of people who are being mean, and that really seems to work. So instead of trying to ignore people who are doing bad things to me, I replace their messages (which are all that I'm evil, basically, in ways that I'm not) with the idea that I'm okay and they're being mean. Of course if I was really doing something wrong, that'd be another story, but when I'm absolutely sure that I'm not, it's not worth twisting my head into knots over. I used to get really obsessive when people said things about me that were hostile or deliberately inaccurate, but realizing that it's their problem and doesn't have to be my problem has made things a lot easier.
Of course misunderstandings happen too, but those are even easier to handle a lot of the time than hostility, because they are generally more amenable to clearing up.
“My world doesn't run like a race so people like me disappear in the shadows. In my world there is substance beyond what's here. In my world inequality's what I fear. My world isn't geared for appearance so people like me disappear in the shadows.” -Donna Williams