I can't offer much advice on this, except Facebook can ban members for a month or so if they post pornographic images. This would only serve as a minor inconvenience though not much of a punishment. Sharing those photos on Facebook is incredibly stupid. Good luck to any future relationships for your ex if they find out they have been posting these of you, what's to say they won't do it to future exes. No one would want to date someone who does this. Their friends will also think they're a moron.
There was a case recently where the owner of a site that republished these types of images got jail time but I assume it was in America and that he was extorting the victims to remove the images, I haven't looked into it though and cannot really research it at the moment.