What about the people who do live single life, who do want their real-life relationships to follow them on-line? Why should we bow down and twist our system for the unfortunate minority that has a stalker problem?

There are ways to deal with those that don't involve designing the entire experience around the special cases. So someone has a restraining order against a stalker. Then it should be enough for them to be able to send a scan of this order to Facebook to mark themselves exempt from real-name policy. There is need for such a problem to influence the way most people experience the service.

Besides, what good does changing profile name do anyway? Even if you'd have a pseudonymous account, you still probably have your real-life friends added on Facebook. Any stalker worth the name will quickly find you by just browsing through friendlists of your friends (if you have a restraining order against him, it means he interacted with you enough to know some of your real-life friends).

You can't solve this problem by changing the service mechanics without ruining it for everyone. This is a kind of matter the police is supposed to deal with, and this in fact is an argument for more cooperation between Facebook and law enforcement.