Breaking Up is Hard to Do on Seinfeld

From the Seinfeld: Dictionary:

Bad Breaker-Upper - someone who ends a relationship by saying mean things that people don't generally mean - but means them

Break-up By Association - what happens when a man and woman break up, and the man's friends no longer associate with the woman

Pre-Emptive Break-up - when a man anticipates that his girlfriend is going to break up with him, so he breaks up with her first

Stab Worthy - a man that routinely gets involved in bad relationship break-ups, and gets physically injured in the process, due to his below-the-belt insults