Adult friend finders.

I have an issue with an ex boyfriend. He wanted a sexy picture of me when we were dating and I was hesitant because I have heard horror stories. He finally talked me into it after promising in an email that he would never show it to anyone and would delete it after he looked at it. We later broke up. He started threatening to post it on the internet. Then he would tell me that he deleted it. He threatened to put it on adult friend finders. I got an email today from adult friend finders someone started an account with my email address. He sent me a link a while back that said it was legal to use someones picture if they send it to you. But I don’t think that means if you agree for him not to show it to anyone and then delete it and also what can I do about him sigining me up on an adult site with my picture. I have married someone now and don’t want him to know about this creep yet he keeps tormenting me.