This is a good starting point for the medical definition of depression (https://www.nimh.nih.gov/health/topics/depression/index.shtm...). Note the variety of treatments proposed that don't involve psychotherapy. These treatments aren't people taking the easy way out, these treatments are for people treating chemical imbalances in their brain that make it difficult for them to function in their daily lives.
For a more lighthearted discussion of depression, the new podcast "The Hilarious World of Depression" features interviews with comedians who suffer from depression, and how they've struggled with and managed from the disease.
This is tautological, and hence true, but an uninteresting point. Just pretend it says "... Depression is when you feel down even when all is going well except of course for the disorder in your brain."
- Depression is when you feel down even when all is going well except of course for the disorder in your brain."
I'm saying this is not a possible situation. The disorder is a result of things not going well, including your own physical health.
Sorry, but that just isn't true. People can be depressed for no reason whatsoever. See my reply here: https://news.ycombinator.com/item?id=13367913
Depression means, even if things are going well, you can't feel good about it.
That just means you cannot identify the reason you're feeling depressed. If everything was going well (including your own health), you would not be depressed.