When you knock upon a door, it is opened.  Alas, it is not always opened by the one you expect.  You are not alone in this adventure you call life.  Others play vital roles.  All are cells in the body of the Creator, all serving the greater good.  At times you only see your influence upon what is most near and dear to you.  As a part of the whole, your influence and role is far greater than you imagine.  It is not diminished because there are so many others, but increased in value for the greatness you make up as a whole.
 
Realize that your desires may at times conflict with those of others.  Know that all is in perfect order and that order will always reign.  There is a Director of this great play who loves all of the actors.  If you stumble and bump into the role of another upon the stage from time to time, consult the Director.  All will be sorted out in favor of the grand production.  It is the Law … the Law of Love.