If you're still living in the same city? You should support your team, win or lose. But, if you move? Then you can reexamine your loyalties. I was never really into the Falcons or Braves growing up in Atlanta beyond being a very casual fan. Then I lived in Nashville for many years before moving to Boston. The years in Nashville served as a slow-motion severing of ties to the old Atlanta teams. So, when I moved to Boston, I was primed to transfer my loyalties, and so I have.