Depression is something that doesn't just go away. It's just... there and you deal with it. It's like... malaria or something. Maybe it won't be cured, but you've got to take the medication you're prescribed, and you stay out of situations that are going to trigger it.
Antidepressants are very good, but it's a clinical cosh, really. Sometimes you have to be knocked out, just to stop; when you're in that state all you want to do is just sleep, and rest your body and your brain.
Bipolar disorder, manic depression, depression, black dog, whatever you want to call it, is inherent in our society. It's a product of stress and in my case over-work.