Advice for the Modern Man: How Do I Get My Ex To Leave Me Alone?

The post-breakup world is a wasteland of emotions. While communication between the two parties should cease as soon as possible, a certain amount is necessary, so each person can process his or her feelings and gain closure.
But there’s an etiquette to these exchanges — what you can say, how often you can say it and how long you can say it for — and whether you got dumped or did the dumping dictates how you are to conduct yourself.