Yep, we definitely had one of those. She believed she was the only 'real one' and that all of us were figments of her imagination. She used to get so upset and distraught about it. She hated herself for losing control and 'pretending to be all those others'. When she fronted in therapy she would spend all her time trying to convince the t she was the only one, and when she was out at home she spent all her time destroying any evidence she found of others. She was a very sad and tortured figure really. Poor soul!