5,762,000 minutes til death. And there better be cigarettes in heaven, or I'm not dying

I spent yesterday in bed, sick. I'm the kind of person who refuses to be sick until I'm sick enough to believe it is possible I could die.  "Do you have a cold?" people ask me.  "Yes. But it's not heart disease," I answer, which elicits some stares. I can't lay around because I have a cold or the flu.  I can only lay around if I convince myself that my cold or flu is the first stage of brain cancer.  Then I can lay on the couch and watch tv and wait for death.
No one told me that quitting smoking causes depression.  I'd read that quitting smoking could lead to "depression-- a sense of loss, a feeling that you're missing your old friend" which doesn't sound like depression at all.  It sounds like a bummer of a day. I don't get depressed when my old friend leaves. I get bummed.
My depression feels like the brain monster my grandfather used to make. He'd grab my head with his thick fingers and squeeze and release until tears came to my eyes. I was certain that my skull bones could not be thick enough to hold up against my grandpa's hands. In those moments when his fingers would press against my temples ("the brain monster is eating your brains") I would squeeze my eyes closed and live in the knowledge of crushing bone piercing my brain. That's what my depression feels like.  That at any moment the brain monster (parenting, my job, my writing, my dishes, my hair, my kids, my dogs, my sad, broken down pos car) could crush my skull, and I would feel the pain of the bones pushing into my brain matter.  So, there's nothing to do but wait for the monster to win.  To lay and wait for the brain monster to eat my brains.
Had I known that quitting smoking would trigger this kind of depression (not the aw, shucks, I miss my cigs! depression-- why do they even call that depression?) I'm not so sure I would have quit.  I don't feel like my cigarettes were my friends.  I feel like I have no need for friends anymore if I can't be friends with my cigarettes.
Dramatic? Why, yes, I am.  It's the flu-cold-brain cancer. It's the fear that it will always be like this. There's no end.  There's no cure.  There's nothing you can do but wait. There's no point in even trying.