Most pain seems to be inflicted by thoughts, rather than anything physical or actual. There's a certain limit to physical pain, were your body either dies or gives you an adrenalin rush, which'll both stop the pain.
To psychological pain, however, there seems to be no limit or end, as you could call it. You could literally ponder over something for hours, with nothing changing. Whether that'd be thinking about something you did (wrong?), or something that might possibly, though probably never, happen. Your body won't suddenly turn and be like: "Hey, let's stop these thoughts." That's because you're so into these thoughts, your body can't sto