Hi, crying inside, and welcome to Psych Central! I am wondering if he somehow got access to such materials while incarcerated and used them as stimulation. After all, he had no access to women. Now he is "addicted."
I don't know, it sounds to me like he wouldn't mind returning into custody. I have heard of folks who get comfortable there and feel uncomfortable when they are released. Just a thought.
I am sad you are going through this, since obviously you stuck by him and looked forward to his getting out and being with you again.
He will need to agree to change his ways--and as was said, that won't be easy.