Granted, these stories are somewhat larger than life, and obviously fictitious. Still, they bring out how major these effects can be. Under the same circumstances, would you be able to say you wouldn't do the same thing? It is mostly about control, but it has a lot to with the expectations themselves as well. Just because someone seems to be able to handle it, doesn't mean that it is fine to go on hounding them.
Everyone has a breaking point, and it is just a matter of time before everything bottled up explodes or implodes. The problem here is not whether or not the person can handle it. It is whether or not you are able to put yourself in the other person's shoes. If you can't do it, who are you to be expecting someone else to?