SIBS, or Scumbag Internet Blues Syndrome, is a state of depression or disappointment resulting from finding a person of the opposite sex online, while knowing that you could never actually meet them in person because they are out of reach or "on the other side of the world".
Bartender: Hey, man, you look heartbroken. What ails ya?
Internetter: I've got SIBS.
Bartender: Ouch, man. Where is she?
Bartender: Damn, that's cold.
Internetter: Shut up, you don't know how I feel...