Obstruction can be caused by so many factors - perfectionism, distraction, faltering confidence, external demands and pressures. At some point, of course, you've got to push through it all if you're to write, and if you don't, or can't, you're sunk.
Everybody's always living in fiction just as much as children, but the way our stories are faked is curtailed by all sorts of narratives we take into our own lives about what are the true narratives and what's not.
I remember going to a son's friend's bar mitzvah, and the text that he chose to explicate was right at the beginning of Genesis. It was not about a fall from grace or a fall from perfection; it was about an awakening into consciousness, which is what it means to be human.