“Many families who resort to scapegoating are headed by narcissistic parents who lack personal awareness, and empathy for their target, as in their eyes, the target is there to serve their false image and make them look good.  So the purpose of scapegoating is to allow families to carry on unhealthy behavior patterns, and maintain the myth of normalcy, without having to look inward or take responsibility for a toxic environment.  To the outside observer – and possibly the Scapegoat – these families seem crazy making and delusional.”

http://glynissherwood.com/12-steps-to-breaking-free-from-being-the-family-scapegoat/