For me, it was like a thick, almost palpable, suffocating black cloud enveloped me, cutting off every glimmer of light or hope. In such a state, a person really needs protective intervention, not the "freedom" to destroy themselves.
Myself, I did not receive such intervention, but I stumbled out of the depression--- how, I do not know.
I went through a period of depression at one time in my life. I thank God I am here. Often, but not often enough, I start the morning by thanking Him for this new day.
My experience is why I believe that we must look out for those around us, who may not know or believe that there are others who understand.