Barney's Past

During episode 15 of season one, Barney admits to the group why he always wears a suit and tie.  Barney explains a past relationship he was in with a girl named Shannon.  He and Shannon were madly in love, planning on going to Nicaragua to participate in the Peace Corps program together.  Right before Shannon and Barney were supposed to leave, Shannon told Barney her father would not let her go with him.  Barney then left to go to Nicaragua by himself, only to come back and find Shannon making out with a clean cut alpha-male in a suit.  This guy was rich, and it was obvious by his appearance.  Barney then decided to cut his hair, clean up, get a job, and wear a suit all the time.  Below is a picture of the old Barney, and Shannon.

Thank you to http://how-i-met-your-mother.wikia.com/wiki/Shannon for this photo.