It's about people who are defined by their pasts or the longtime roles they have assumed. Clinging to these definitions of themselves has made them unhappy and unfulfilled in the realities of their current situations. They meet someone who they believe could have fulfilled them if they had only met years before, when they were that "rock and roll" person. However, now they are too "far away" from that moment of opportunity. The "happy endings" are both about other people who manage to seize that opportunity at the right time before it passes them by and--quite possibly and more importantly--the realization of the people in the song that they are past that moment and definition of themselves so that they can now move on and embrace their current realities. The song's chance encounters are about both regret and revelation.