You're showing a complete lack of knowledge on the subject. Clinical depression has been accepted as a physical condition for many years. You're at liberty to disagree with established scientific principles (many of which have indeed been shown to be flawed over centuries of research) but I'd hope you might at least have some basis for your opinions.

So far you have rather given the impression that you believe clinical depression to be somewhat the same as you might feel when your dog dies or your girlfriend dumps you. When you're clinically depressed you don't need any reason at all to feel that you're in an endless pit of dispair. You don't have the option of taking a deep breath one day, saying to hell with this, and making yourself feel better. Emotional instability is just the symptom; the cause is a serotonin or other chemical imbalance - a physical, measurable condition.

I don't speak from experience but I have had this described to me by people who have mattered to me. I sincerely hope nobody close to you suffers from this condition if all you can do is patronise them.

Rob