I've crossed some kind of invisible line. I feel as if I've come to a place I never thought I'd have

I've crossed some kind of invisible line. I feel as if I've come to a place I never thought I'd have to come to. And I don't know how I got here. It's a strange place. It's a place where a little harmless dreaming and then some sleepy, early-morning talk has led me into considerations of death and annihilation.
----Raymond Carver, Where I'm Calling From: New and Selected Stories