"When a patient tells me his mother thinks something's wrong or his buddy thinks he's 'crazy,' I tend to pay attention to that. These people have insight that I don't."
That quote came from a therapist friend of mine a few years ago when I was first becoming active in mental health advocacy, and the idea has since stuck with me. It just makes sense.
When your mother notices your moods have become alarmingly erratic, or your husband becomes concerned because you no longer want to do anything that involves getting out of the bed and showering, or your best friend can't get you to do any of the things you used to love doing - these are all situations in which the people who spend the most time with you might be picking up on a problem. These are all situations in which these people can actually help you - even if they're just helping you recognize the possibility of a problem. Sure, it may tick you off ("You're overreacting!", "You don't know what you're talking about!", "You're not even a doctor!"), but you trust these people. Chances are they have your best interests in mind and they're not going to broadcast your business or use your troubles for their own personal gain (as opposed to the media).
Bottom line: When it comes to your mental health, sometimes an unsolicited diagnosis from people who are close to you (as opposed to an unsolicited diagnosis from the media) can be pretty helpful.
But what happens when you get an unsolicited diagnosis from a professional via the media?