I'm very torn on your situation Ragab. On one hand, I'll be honest, if you guys are still this angry and torn apart 12 years out from Dday, then I'm not even sure why you are still together. Why are you still together?
Here's the thing though. I don't know you or your story, and 12 years is a long time. Lots of people here will tell you that each spouse has to heal on their own (their own effort, and time) and you can't "help" your spouse heal from the trauma any more than you can help them heal from a broken arm. That much is true. However, what is also true is that you CAN hinder their healing. To use an analogy, if someone stabs you with a knife, you can heal from that, however, the person first has to stop stabbing you. What many WS's don't seem to understand is that their own inability to own (really own, not just admit) their choices and actions, and things such as minimizing, trickle-truth and defensiveness, are all actions and responses that keep the knife in the wound. Your spouse can't heal and learn to trust and love you again when you are still hurting them, despite whatever justifications and excuses may exist. "Get over it" is not a path toward healing.
In the first few years after Dday, I felt exactly the same as you do now. I even asked those very same questions. It seemed pointless to continue in a relationship where all I could see was me losing every argument and being blamed for everything for the rest of my life. However, the truth is, that was my "shit attitude" talking. Yes, it is totally fair to not want to live such a life, and certainly, most WS's find themselves in this very position initially. There were many days that I felt that simply saying "Have a nice day!" might be met with (for example), "Don't tell me what kind of day to have! Every day is a shitty day and that's your fault!" And it sucked.
All that being said, that is not how life is today. We are just entering year 7 after Dday, and I can tell you with 100% honesty that my wife NEVER NEVER NEVER throws the affair in my face. I win and lose arguments based on the merits of that argument, not my past behavior. We make mutual decisions and those outcomes are based on both of our needs, and there are times when each of us sacrifices for the other. When she's wrong, she apologizes and makes things right. There is no scarlet letter on me. I am not a cheater, I am a person who cheated, and we see our relationship as an ongoing story, of which the infidelity was simply a chapter in that story. We are now in a new chapter.
Don't get me wrong, we discuss the affair when needed, and do so openly and calmly. The pain and the scars are still there and always will be, those things don't go away. The affair will never be "okay" and forget about "laughing about it someday". But since everything is out in the open and there is no defensiveness or attempts to gaslight and control the outcomes, it creates a safe environment that we were both able to heal in. In fact, in many ways, our relationship is much stronger. It is certainly more honest, and I feel as though we "See and hear" each other much better these days. I used to do nice things for my wife because I wanted to be special in her eyes, I needed that attention. Now, I do nice things for my wife because she deserves it, and because I want HER to feel special. I can feel special on my own, and don't need the approval and praise of others to feel good about myself. More than that, I can feel badly about my mistakes and poor choices without having to define my entire being as a "bad person". Even good people fuck up now and then. The difference is, healthy people own their fuck ups, and unhealthy people hide behind fear and anger instead.
All that being said, it sounds to me as if you still have work to do. Not on her, not on the marriage, but on yourself. You still clearly seem to define your own worth from her perspective of you. And that's not helping anyone. Do you know your "whys"? I mean really deep down, do you know why you cheated? If you answer, "because I wanted to" then you need to dig a LOT deeper. You need to decide who it is you want to be in this world, and who you DON'T want to be, and then learn to love yourself enough to go be that decent person. Once you love and respect and value your own integrity and decency and actions, then no one else can make you feel like shit about yourself, ever. If you feel like shit, it's because you failed to live up to your own high standards, not because you don't meet someone else's expectations.
I wish you the best. There is no handbook for this shit and so working through it is hard. Having people like the ones here, who have walked in your shoes and made the same mistakes, is so very helpful and valuable. Please keep coming back.