This kind of attitude is exactly the reason I took so long to tell anyone when I started getting symptoms of depression. Whether or not it's true, there's a very thin line between complaining about over-diagnosis and encouraging a very damaging stigma against people with what is, at the end of the day, a mental illness they can't help.

Secondly, when I did finally get some help, the absolute first thing I was told was to try exactly those things -- improve my sleep, diet and exercise. Your problem is with the attempted treatment you've seen, not really the identification.