LonelyGuilty
I'm sorry to hear that you are struggling. The truth is, it is year one, and the pain is so overwhelming for your BS. His entire world was crushed, and right now, he is unable to trust anyone or anything. The person that was supposed to have his back... stabbed him in the back instead. Nothing feels real to him anymore, nothing feels safe... not you, not even himself.
Do this. Go to the market, and purchase the loveliest, fanciest cake they have in the bakery. Now bring that home, and place it on a carpeted floor. Next, go get the muddiest pair of boots you own, and then stomp that cake into the rug for about an hour.
Now, make the cake edible again.
As WS's, we often have this fantasy that somehow, we can save the cake we just stomped on. But the truth is, we can't. It doesn't matter what you do, what you say, how you act, or even why... the cake is gone. It can't be saved. And while I know this seems obvious, it often isn't. Our hope remains.
Nothing you do right now will be enough to "make it okay". To be honest, it is likely that even your spouse is unsure what it would take right now for him to feel as though whatever you are doing "is enough", because nothing puts the cake back together. Right now, he (rightfully) sees you as the most selfish person in the world. He saw you put yourself and your wants/needs ahead of him entirely, to his detriment, to his destruction. Twice actually, since you had a second D-day... you chose to hurt him AGAIN after seeing the devastation it wreaked the first time. That's his reality. So yeah, anything you do right now will seem like a manipulation at best, and a desire to alleviate your own guilt more than anything else. It's not that he doesn't believe you... It's that he can't believe you. He needs to protect himself from you, and putting up a wall protects him to some degree.
So is that it? Is it all over? Is there nothing you can ever do? Maybe.
Infidelity is often a deal-breaker. Full stop. Most people cannot and do not recover. I don't say that to scare you. I say it to put a real expectation in your head. You fucked up. Again, try fixing the cake.
If anything will make the difference, it is time, effort, self-awareness, and commitment. Equal parts of all. Since you cannot fix the cake, you need to create a new one. If there is to be a reconciliation, it cannot happen with the person who cheated on him. So you must be someone... better. You do this by figuring out your own shit. In other words, WHY did you cheat? And I don't just mean the superficial, "Because I wanted to. Because I was selfish. Because I was weak." That's obvious. I mean WHHHYYY. What in your life made you the kind of person that would disrespect YOURSELF enough to cheat? Why was that even a thought in your head? I'm sure if you went back and asked your 10-year old self if you'd ever grow up to be a cheating spouse, that inner child would say, "No way Jose!". So what happened? You destroyed yourself, your spouse, your relationship, maybe more. That's not due to boredom. That's not, "I was horny". That's some self-destructive behavior there, and it certainly didn't start recently.
Go get some therapy. Dig deep. Figure out what in your life got you to where you are today. And make positive changes in your life. BE the kind of person who you admire and respect. When you become someone worthy of loving themselves, someone of integrity and decency, then you'll have a shot (maybe) at building a new relationship. With your spouse, or someone else. For now... do the work. Fix yourself. Love yourself.
FWIW, I was shitty WS. I hurt my wife for years while trying "do the right things" because at the end of the day, it was still all about me. Once I was able to pull my head out of my ass and start to see myself for who I was... things finally began to change. We made a new cake together. The old cake is still mashed into the rug, no doubt, that never goes away. But the new cake is nice. We are ten years out and still working on a cake that we can both be happy with. It is rare, but it is possible, and you'll find a few stories similar to mine on SI. If you want that... do the work. And be prepared to fail, a lot.
Best of luck to you. Keep coming back for advice. Not everything here is what you'll want to hear. But everyone here is honest with you. So take it all in, and grab on to whatever works best for you.