I'm so sorry you are going through this hard time, your love to him make it so hard to decide what to do....however, why don't you ask yourself one question: do you love him enough to endure the suspicion of him continuing this fetish in the future even when he told you he has stopped?

I can't tell you what I would have done because I don't know how much you love him, so my action wouldn't be able to reflect how you would do. But this is sick....I understand most men like young girls and all, but he seems obsessed with them to a level that I can't accept. And I would feel so insecure about myself too as I'm not a young girl. Maybe you should take a break from him, not see him for a while until you sort out your thoughts and know what to do. Hope you will come out of this ok