There are different levels to depression, but when you're depressed, you know it. There's an internal collapse. Walls narrow. Your soul hallows. Your days blur. There's lots of licking nacho cheese powder off your fingers as your head grows a permanent pillow. Motivation is someone you used to know, a long time ago. These days you just read about it. Depression is not a teeter, it's a sink. Whether it's sudden or gradual, there's been a shift and you're aware of it.
A depressed state, however, is a slow leak you don't notice. It's a low tire you keep driving on. You know you're unhappy, but it's been so long since you tasted happy, there's no contrast. And you hold on to your sunken state like a baby blanket. You've accepted it. Because over the years, it's taken your self esteem hostage. You no longer believe change is possible or that you even deserve it. The result is a muted life.
Living in a depressed state is worse than being depressed. Lack of awareness dissolves any urge to pull yourself out. You never wake up with the realization that you're not living.
It's a coma I know very well. I lived in it for most of my adult life. For many, this is what it looks like: