I think this is what he told you to save face about being in a toxic relationship. Unless he has a problem or is looking at something illegal, I'd say the average person looks at porn sometimes and that there is nothing wrong with it. Even if he was being upfront and honest, why would he put something like this on his partner? It makes no sense. I have married friends and have been married for 21 years, I've never heard of anything like this in a healthy relationship.