Privacy & Disclosure Boundaries?
I have some questions regarding privacy and disclosure.
I made the mistake of disclosing a specific piece of information/specific experience that my primary male partner (J) and I had last summer (which was in itself a boundary-breaking experience) to my female secondary partner (M) (she and I have been together 3 months). Last summer, I agreed to that I wouldn't disclose this experience to any of our mutual friends. In retrospect I should not have agreed to this because I also kept myself from processing the experience in other ways that would have allowed me to resolve the experience; keeping the agreement felt stifling. I had kept this agreement for almost a year, until I told M a few days ago because the experience came up in our conversations.
Right afterwards, I had a good feeling J would not be happy I told M. I told J when I got home that night what I told her, and he was (understandably) very upset that I didn't keep this agreement and likened my actions to cheating.
Up to this point J and M have been very friendly with each other, and while the three of us have been sexual together, their relationship is otherwise pretty platonic, although friendly and flirty. Now, J says if M knows sensitive information about our relationship (including any details about the conflicts that he and I have) he wants to distance himself from M. He does not want to feel judged by someone that he does not trust or know on the same level that I do.
I can definitely relate to his feelings around this, as I have myself felt uncomfortable when he talked to other dating partners of his about the conflicts he and I had during those times. So I understand his need for some kind of privacy.
At the same time, M is feeling upset about the idea that I won't be talking to her about everything that I want to- including the details of the conflicts that J and I go through. Ideally, I would want M to be just like another very, very close friend that I can confide to about anything and everything. But I also want J and M to continue being as friendly as they were before, and it doesn't sound like this is possible for J.
I have apologized profusely to J for my mistake and he knows I am sorry.
(To add to the stress of the situation, J is incredibly busy right now with school and has barely any energy left over to devote to negotiating and resolving this. So I feel stuck and primarily responsible in finding a solution that feels comfortable for us)
How have other people dealt with negotiating privacy and disclosure boundaries with multiple partners?