I'm not really in the same boat as you. I look at porn WITH my hubby, but I do feel for you.
I know that some women don't mind porn, some do, I'm not replying about that either way.
What I did want to say is that if the two of you are having an issue that hurts you this seriously, no matter what that issue happens to be, he should at least be willing to compromise on it if nothing else.
It is not fair at all for him to be doing something that does nothing but hurt you while he receives nothing but pleasure from it. He really needs to take your feelings into account.
I don't think telling him the same thing over again will do much good. He has to really see & know how much it hurts you & why.
I also think he needs to talk to you about WHY he looks at porn. Maybe he'll make you see that it has nothing to do with you, good or bad, maybe not, but it will at least start a dialogue between the two of you that goes on a different course than the dialogue you've had before.
At least then you're talking differently & what the two of you have said & done before hasn't worked, maybe you'll stumble across something that will.
Good luck, I hope your heart can heal.