how to explain attachment disorder to unbelieving family??

We wrote a letter that explains some of the psychology, explains some of what we see at home and is very clear about the fact that it doesn't show up for outsiders and why. I believe we pointed out a few little cues that outsiders could look for and see that things aren't quite right. Did it help? Maybe. At least it caused people to question their own superior knowledge of the subject and helped to keep them quiet. I think the results would depend on how much respect you command in your family and among your friends.