I myself think this man needs more help than you can give him. Sometimes someone is like this because of learned behaviors from their family members when they were children. But not always. I think he needs some counciling to get to the root of his problem in this area. Meanwhile if it was me. I'd move on. At this point theres really nothing you can do.. except learn from your experiances and know that that is not poly in the slightest shape or form. And i commend you on your strength and willingness to learn more about poly.