That was me. I didn't mean to make it sound like depression is nothing and I definitely didn't mean that depression is just a little rough time.
I have been through it too. I was on anti depressive pills for two years and went to a counselor for a year. Struggled with wanting to "jump off the train" for a long time. I know how horrible it hurts in your soul and what a black hole it is. A hole that doesn't seem to have any light in it at all.
(It came as a result of a very rough childhood.)
My thoughts about depression not being a mental illness comes from people the same stuff that you talk about. It's like mental illness is labeling people and that depression is a pretty common thing after all. (Meaning not as “heavy” as suffering from a psychotic illness.) We all feel ashamed over it (well, most do) and feel like we are weak. So I am kinda trying to say the same thing as you but didn't know how to express it better. Sorry.