Well, if your focus is entirely on "curing" people who have mental health problems, I can see where you'd think everyone is messed up. You're judging by your sample set, which self-selects only messed up people.

That's why positive psychology is so awesome. It says that most people are pretty okay, but that's not good enough. They should be great, and positive psychology has the tools to help them not just survive, but thrive.