question

If you are initiated, you can never join another fraternity (a national one, anyways). If you don't like your house, start trying to make it the house you joined again. Get involved and be a leader and fix what's broken.

Like the guy above said.
Once your initiated into a fraternity you are a brother for life and can not join another fraternity. Unless you petition to your national organization to revoke your status. But if you did that you would basically have to throw everyone else in your house under the bus and even then they still may not allow it.

Are you in a chartered fraternity? If your in one of the colonies on campus (like TKE or Kappa Sig) and have never been through an initiation ceremony you could leave whenever you wanted to.