Humans are creatures of habit. Ever wondered why many people keep themselves in abusive situations even when you, as an outsider, can easily see a method to escape.
It has nothing to do with the intelligence or capabilities of the victim. In the end, an effective abuser understands that to control someone is to make someone rely on them. Humans are naturally afraid of change—in the same way, that humans are naturally afraid of the dark. Both of these fears are simply the symptoms of a much larger fear—the fear of the unknown.
The future a victim is separated from society, the less they know about the safety and protective measures of the outside. Ultimately, they may develop an attachment to their captor because they feel as if their captor is the only one that understands them. As such, it's the only place they feel 'safe', as ironic as that term becomes.
