From the little bit of info you've given us, it's difficult to know the whole story.

If porn is impacting his relationship and his job, one could suspect he has a sexual addiction. Depending on his job, he could be fired for having porn at work. He could also be spending a lot of money on porn.

Have you talked to him about it? He needs to work on putting the porn aside and work on focusing more on his real relationships, etc. Would he consider counseling?

S