Issue 1 - Doesn't sound like a thing has sunk in.. and Issue 2, he's emotionally manipulating you. Of course you're not obligated, you're a human being and you do not have to do anything you do not want to do. I bet its not written in your wedding vows.. 'thou shall give into my husbands every sexual whim'.

If it were me, I'd have told him to sod off, and stick to porn. Sounds like he's a bit of a sex addict and has problems. I only say this because he's not listening to you, or respecting you, so then it equals a problem. Of course you're not responsible for him if he doesn't quit porn, no more responsible than him looking at it. He's a grown man, and all of his actions and decisions are his own. Its just ludicrous quite frankly for him to put all of this on you. Sorry, sometimes I do not mince my words, apologies if I sound bolshy.

There's so so very much more to marriage, and of course you than just sex.

What are you going to do?