B.M.
Hi, Please check out these web sites.
http://www.attachmentdisorder.net/Symptoms_Causes_Researc...
http://www.attachmentexperts.com/whatisattachment.html
It's frustrating not knowing what to do or how to help. I have an autistic son and remember the feeling well. Go on the web and read all they have on this disorder. The key seems to be making the person feel secure in themselves so that they can loosen the attachment a little and interact with others.
Remember in this case as in most others knowledge really is power.
Good luck.