Why did this guy freak out about me simply asking people about their depression?

I have depression. I go on to this online site for something, and it's a message board. I create a thread asking people how they cope with their depression, when this guy came and rudely said that he wasn't a fan of my post and how he's not depressed, how he has all these friends, blah blah blah. I mean, if he doesn't agree with something that doesn't apply to him, why did he freak out about it? It makes me feel weird because, well, I have the right to ask people about how they cope with something that I go through... If he's so darn happy, why did he take offense to what I wrote about something that doesn't even APPLY to him?