I (31M) have to accept cuckoldry suggested by fiancee (27F)??

Cheater being told cuckoldry is the only way to continue relationship.

I (31M) cheated (emotionally) on my fiancé (F27). First and foremost, I'm not making excuses and am staring it head on. All via text, for just about a year. Yes, shame me. That's okay. I know I disrespected and disappointed my partner.

I found out that she is doing the same thing, a month after she found out. She found out mid November, and started on Dec. 16th. I told her straight up that I understand, this was caused by me, and that I do not hold her responsible for it. The only real part that bugs me about it, is it's way nicer and cute and flirty than she's been with me in the past 3 years, she consistently asks him for selfies, couple nudes / videos, and she asks how his day was (Aside from me disrespecting her by cheating on her, we felt like we were golden and nothing could touch us, so I guess I'm just upset I never got to see any of that myself. I probably do not have a right to be upset, and I try not to hold it against her).

I had gone through the messages, and I had asked her "To block / get rid of him in order to help me clear obstacles in the path to our recovery and rediscovery." She had stated that the obstacles were introduced by me in the first place, and that she should have every right to do whatever she wants while she figures out what she wants.

This was going to be my first monogamous relationship since I was 16 (we got together when I was 27). And then yes I screwed the monogamy part up. I did it. For a year.

She feels that I should allow her to keep talking with him while we figure out a path. I feel like this is just cuckoldry.

I'm not asking if I deserve it. I'm not asking anyone to blame her for anything you may perceive as immoral or bad choices. In fact, I'm not even asking if I should stay with her. I'm glad she has come up with something in her brain, it shows a level wants to stay and work it out. It's all my fault anyways.

This is my person. Regardless of my faults. I will be pursuing passion with this individual for the rest of my life, through the ups and the downs. What I want is advice on how to compartmentalize this all so I can stay healthy and productive in life and our relationship. We just went to have makeup time, and I was unable to stay "attentive" because I thought of cuckoldry.

I just want tips, please. I'm working on being a real man. In the meantime, just help me with the mental aspect of this.

-E