This is my first ever post on here and as I guy I felt compelled to comment. I'm sure I might get some crap for this but it's just an accurate representation of my relationship with porn. Firstly, I'd like to highlight that there are a lot of men out there addicted to porn and excessive use results in some worrying side effects in men like erectile dysfunction etc. If a guy is under the age of 40 and having erection problems it's almost certainly that. That does not even mention the fact that guys start watching porn at such an early age ~13 before they've had any other sexual experiences. This is not your playboy magazine kind of porn, it's high speed internet porn. Any fantasy, any place, any time. Asking a man to stop this will seem like an attack, he will agree then feel forced to hide his behaviour. If we lived in Candyland, he'd stop but this is the real world, shit is hard.
Now think when these men getting into relationships, they have consumed thousands of hours worth of porn. I am one of these men, it's only recently that I've seen the trouble it's caused me. The reason why I have highlighted this on this post is because telling a man to stop or your leaving him will not make him stop. It's almost like a drug addiction, threats will fall on deaf ears because these men need to be shown that there's a way out and porn is damaging their brains. But it is reversible, my sex life is normal now, after I quit porn I went through a really bad patch, then I started really enjoying sex again. It was like being a kid again and discovering sex for the first time. So if you have concerns with your other half about porn, try to understand that he may have been watching porn for so long he just doesn't know anything else and help him through it.
If you want to do more reading on it, there are plenty of studies online about the relationship between porn addiction and what it can do to the rest of your body and your mind. I understand I haven't even touched on the content itself but it seemed pretty well covered. Most men don't even know the benefits of quitting porn, so present it to them in a tactful way. Communication is key here because both of you will reap the benefits.
Good luck