Life choices are a little different when we have people depending on us.  It is one thing if we fail our self, but it is more serious when we fail others.  David was on the run from Saul when he wrote some of the Psalms.  Along the way, 400 men and their families joined in with David.  Now David had a small army he was responsible to feed and protect.  David was on the run for several years and learned how to trust God in the most difficult of circumstances.