Slang term, origin unknown from the 1920's in America. Used to underline a failure of an action, or dissapointment in reaching an undesired result, with the additional meaning that the result was not an unexpected one.
1. The feeling you have when everything is crumbling around you or when you have the feeling that it is.
2. Another word for depression or a sense of impending doom
Gordon: Gosh I just feel like everythings crumbling around me
Dr. Coomer: Oh dear Gordon, that sounds serious. You may have come down with a case of "The Crumbles"