It's probably that there's a deeper reason, and either the husband and/or wife is just using porn as the pre-text for the marriage problem.

The bigger question is, is his wife giving him enough sex? Maybe that's why he's turned to porn he's sick of being turned down by his wife, the poor guy just wants some tail. It's better then him going out cheating on her.

This is the point where he needs to choose between his wife and his porn addiction.

One fight will for sure be a lot harder and require years of willpower, but be well worth it. I hope he makes the right call.
That said, a supporting/forgiving wife will help him a lot along the way.

Strange question. It's about their sex life, so of course it affects her. There are many couples where it's no problem at all, but when you're seriously addicted your sex life goes down the drain. Real-life women and "normal" sex don't reach the threshold to excite you anymore. Then there may be other reasons - maybe she thinks his preferences are disgusting, his porn is misogynistic, he no longer has desire for her, ... we don't know. Some people feel watching porn is just as bad as cheating, some don't care. But if it's serious enough for therapy their relationship must have been suffering badly for some time already.

She is banging another dude, wants to get rid of her husband and now is using that as an excuse.

The fact he is addicted to porn means his wife does not cover him sexually or even worse they can't match on that!

My wife doesn't care AT ALL about my porn collection. I have over 150GB of porn in my HD and, in fact, she watches with me. And sometimes she even wants to watch them alone...

I don't know, I'm not sure how that would be a problem. But it's their life, so I'm not going to try to solve this.

How old is his wife, by the way? Mine is 20 years old, and I completely agree with you on that.

They already made a movie about it.

http://www.imdb.com/title/tt1207648/

its worth the click