Background: My partner has a severe history of infidelity. We've been working together and separately to heal, learn, and grow. It's going well (or I thought it was.) We have an ENM/CMN pseudo-open relationship. Agreement number one is complete transparency and honesty.

Today, he told me that one of his trysts had contacted him again, and he wants to reply and start talking to her again.

We have boundaries and agreements; one agreement is that we leave the past in the past to move on ETHICALLY and support rebuilding trust...part of which means no contact with anyone he has previously lied about or cheated with.

He lied about her in significant ways, lied to her about me and our relationship, and cheated with her...(sexting and graphic photos count as far as I am concerned because of the lies and betrayal.) ...even when I asked him directly about her, he lied to my face. It didn't make it to in-person physical sex, but the lying and hiding it all from me, I consider cheating, especially considering how sexual it got via Snapchat, etc.

(Just for reference, I don't expect all the details, but I have a rigid boundary around lying and hiding things. I am a proponent of informed consent and respecting other peoples' boundaries and privacy.)

Now he wants to "see where it goes," and it is excruciating and triggering for me.

Am I being unreasonable in asking that she stay in the past and he remains entirely no contact? Neither of us believes in veto power, but I don't think this is the same as a blatant veto. He wants this so bad that he is willing to break our agreements and bring all of that betrayal and pain back for me. He tried twisting my words and saying things like, "Wasn't it you who said you don't believe in vetos?"

I'm really hurt by this, but I know I might be wrong. Please share your thoughts, advice, and stories. I'm feeling that betrayal all over again. Why wasn't it an easy no? Why is he willing to hurt me all over again for her? He says it's not like that, but it is for me. I don't know where to go from here.

This person stood him up and ghosted him. Her message this morning was an apology for doing that, and suddenly, he is so interested even though he was trash talking her when she stood him up.

When I asked why he wants this so bad... He says, "Because she's nice and cute."

He also said something else that really bothered me. He said, "It's a good thing I told you so we could actually talk about it because otherwise you'd have never known. It could have been so much worse, and you know it."

I honestly don't know what to do. I don't want to give in AGAIN and just let him walk all over me. I'm pretty sure he's using DARVO to get his way by twisting my words and guilting me, calling it a veto, and saying I don't understand compersion. But really, I do!! I have been so happy for him as he's making new connections and getting out there on dating apps. We've even been talking to a few couples in our area, trying to make new friends and explore this world more.

Do I uphold our agreements and boundaries or do I just let this go? He keeps talking about how he has never vetoed me and never would... Even though this is literally written out in our agreements. Am I wrong? AITA here? I know I have more work to do in general to heal and learn and grow...but my gut is telling me this is wrong. Am I just biased/jaded?