DCP, perhaps it's your fault and perhaps it's not. We all have days when the balls don't break for us even when we're hitting the one square. Still, I think that if you are defining success as consisting of a run out and a run out only, then you are shortchanging yourself. Why not, instead, define success as either a) running out or b) finishing your turn with a well-played safety that, in a competitive situation, would make you a big favorite to win that rack? Remember, the player who knows how to control the table is a consistent winner in nine ball. You don't always have to run out to win! Go for the runouts that you'd go for in competition, and play safe when it's called for, even in practice. It might help your self-image.
Go a little easier on yourself.