You mean the 50 ways to leave your lover? The song kind of speaks for itself, doesn't it?
On a more serious note, recapitulating sexual relationships/events helps free up energies you may have invested in these "lovers" and helps both you and the partner "move on" so to speak. It helps you both, even if the other person resists this at first. If you don't actually dissolve the lines of energy, they may react in a way that is much more painful for you and a waste of your energy. If you do your part, then they are unable to maintain the connection, just as would be the same if they "wanted out" and did the same on their own.
As far as dropping off the key and hopping on the bus, this may or may not work and they may still follow you around energetically, Gus.