This is a good summary of how depression manifests itself in teenagers, but the online social component is missing. Depressed teens lie online, they change identities daily. I once had a case where a teenager pretended to be his mother on AIM so I could give him positive reinforcement on how he was doing in my program. In reality, his mother yelled at him to get off the stupid computer. Depression in teenagers also has a lot to do with their parents' problems, whether it be divorce, alcoholism, or worse.