Everyone has some type of symbolic door they long to enter. For one reason or another they must stand outside and decide if they will walk away and never look back, or if they will stand and stare at it pointlessly with longing and anguish knowing they will never be able to knock because they will never be able to enter and cross the threshold.
This is my door today that I very much desire to ring his bell, be let in, be a part of life on the other side, the person who is there. Pursuit beyond this door would be wrong but I can't look away.