We all live in the past, because there is nothing else to live in. To live in the present is like proposing to sit on a pin. It is too minute, it is too slight a support, it is too uncomfortable a posture, and it is of necessity followed immediately by totally different experiences, analogous to those of jumping up with a yell.
Certain people, in their eagerness to construct a world no external threat can penetrate build exaggeratedly high defense againts the outside world, againts new people, new places, different experiences and leave their own world stripped bare. It is there that bitterness begins irrevocable work.