THANK YOU!!! Thanks for sharing your story and for also making me feel like I'm NOT the only person in the world who is bothered by this. And that I'm normal for having the feelings that I do. Gays these days are so judgemental and unaccepting of anything that doesn't fit their own views and experiences, which is so so SO hypocritical. I'm sorry to hear that your relationship went sour. Fortunately, my sex life is incredibly healthy and seems to become even more healthy the longer we date. The opposite of what everyone says will happen haha. I guess I'm just afraid that it would eventually lead to where it lead your ex (the porn not being enough). I guess I will take this as it comes, and see where we end up!
And that's why the control starts! Fear! The future is scary, and you can do your best to protect yourself for the future, but when it comes to your significant other, sometimes you simply have to trust and let go of the wheel from there. It's been fairly set in stone, you've expressed your feelings, he's expressed his feelings, yet the porn continues. You don't understand it, but he does, which leads to hiding. It's a toxic weed that can bloom into you two ending, all because of "what could happen."
Other perspectives, he could cheat on you without looking at porn. Someone earlier said how do you know he isn't cheating on you when you're away? That's trust. Embrace the trust you do have, he's promised monogamy to you, and it's up to you to trust him and expect him to keep his word. The sex is great, he's great, sometimes he's alone and wants to look at porn. Honestly broadening the spectrum, porn isn't much different than him jacking off to a mental image of someone else. It's visual stimuli if you're feeling uncreative/lazy. Hell, if you want to lie to yourself to feel better about it, you could even thank porn for him not going out and finding the real thing outside of your relationship.
Regardless, his brain is wired a bit different than yours, so is the case with anyone in any relationship. You don't have to accept it. You just need to understand it, and make a healthy sacrifice on your part if you wish to continue your relationship. And I'd say it sounds like a great one!
In my case, I don't believe it was porn that lead to the other things. I believe it was the smothering, which started from me being "hurt" all the time when he'd look at porn, which he was ridiculously open about, and I didn't realize that was something I should have embraced. The honesty, before the dishonesty. It was so many arguments about him finding someone else that may have lead to that exact decision. I'll never know! I can only learn and apply from it. So I'm really glad to hear you're going to roll with it, would hate to see that happen to someone else over something so fickle as porn.