How do I help?

From what you say, it sounds like you care about each others. That's amazing!
It's hard to tell what exactly might be helpful, but having your support, he's really lucky. Keep up with your positive feedback, and at the same time remind him that it would make you sad if he relapsed.

You mentioned that he talks about a relapse as a reset. It's great that he's conscious of this! He's right: it's his brain tricking him into thinking that way. You feel a brief relief after relapsing, but it lasts seconds for the cost of starting all over again from almost zero. Urges come away after some time, that's a hard fact! Sometimes it gets longer, sometimes shorter, but they go away and you have more stregth to fight on.

When I had really hard urges, I took cold showers (like, really cold).
I would also work out, meet friends.
I would go to church and pray a lot (I'm saying that in case if you're religious).

Either way, you sound like a great support to him. I know how hard it was for my wife, and we're happy together after all the effort, so I'm cheering for you too.

 

This is not your problem. If he knows he’s struggling then he needs to take action, it is not in your control.

 

If he relapses its not your fault, its his! He needs to find healthy ways to deal with his porn brain not you. this is on him and has nothing to do with us

 

I agree with the next two posters that it is his problem not yours, but you asked whether there is anything you can do to help and that remains a valid and loving question. For me, the secret is to avoid screen time alone. If I sit around with access to porn just one click away, eventually temptation will win. Getting him to pursue interests away from the screen, either alone, or with you, should help him. Try to help him limit his idle time and create new healthy habits.
Good luck

ANH