Tldr: my ex gf hooked up and had a falling out with a mutual friend, breaking our agreements after we separated. Now as my friend, my ex is upset I haven't agreed to never hooking up with the same friend out of respect for our friendship. Wibta for being open to having sex with my friend?

Hypothetical wibta situation. Shane (25F) and I (25F) had been dating for about 7 years before ending things semi-mutually a couple years ago. We'd been friends since we were kids so since separating we've been attempting a friendship rather than romantic relationship and adjusting to boundaries and whatnot being different with each other. We've been semi successful at this and generally get along well, with the exception of a couple topics.

One thing to note about my ex is she is veeeerry sapphic and does not really enjoy men at all, especially sexually. She's friends with some men oc but really dislikes them generally and definitely is repulsed by penis. Its caused a tension point with me dating my current bf and inviting him to events that she's going to. Even so, back when we were together we were good friends with another couple Jenny (F) and Max (M) who we saw regularly and became very close to in a couple years. When we separated I ended up moving back to my home state for a while and she stayed, so naturally she kept spending time with this couple, especially Jenny (who is bisexual).

Another element at play is Shane and I had been attempting to practice nonmonogamy for a couple years and Jenny was interested in exploring threesomes and playing with other women. Shane and I discussed Jenny and Max's dynamic and both agreed we had some issues on the ethics around Jenny pressuring Max into accepting her cheating in the past leading to an openish structure where she's able to kiss and engage somewhat with women with his "consent" (according to her on what they've agreed to). For that reason, as well as the general closeness of the pair to both of us individually, we mutually agreed to not further engage with Jenny and Max sexually while were together. Upon separating we agreed we wanted to stay friends and stay in each others lives, so I naturally assumed agreements in place around respecting these friendships would be upheld as well.

Long story short, I found out from Jenny a few months after I left the state that within a couple months Jenny and Shane drunkenly hooked up while Max watched. I found out because on the first night of Jenny's bachelorette party (I did not go) Shane was allegedly attempting to hookup with Jenny, and after being turned down, ended up hooking up with one of Jenny's good friends later that night. This exposed some deeper feelings from Jenny and blew up their whole friendship, who after the trip told me the whole story and roped my into the drama about why Jenny and Shane wont be friends anymore.

Shane came around and reached out a few weeks later to talk about things (mostly unrelated but she mentioned Jenny wouldnt be in her life anymore). When I said I knew cuz Jenny told me, Shane then defended herself with her side of what happened which I could understand and sympathize with to a degree. What I couldnt get over and havent still is that Shane hardcore blamed alcohol, emotionally rebounding, and being preyed upon by Jenny, but has also shown an immense amount of attachment to Jenny that I'll admit hurts to see that extreme of attachment when she barely seemed rocked by our separation in comparison. Shane also didnt tell me and I dont think wouldve told me what happened if Jenny hadnt already given me the information, so my trust in Shane respecting me as a friend to tell me about something that effects my relationships has been damaged (I was talking to Jenny all throughout the months before the bachelorette, Shane and I were not in contact besides need to know details like around our dog).

Its about the year anniversary since this whole bachelorette drama happened and Shane and I have been hanging out and doing activities together. This last weekend we were out partying (so I was very not sober) and I brought up a discussion I had about swinging with my bf and this couple (mostly in a- is the energy of this couples dynamic something we'd be interested in since we can be picky queers). Shane got upset and was like, but out of respect for our friendship you wouldn't hook up with them ever, right? And personally, I'm autistic, forever has a lot of possibilities that I cant account for so idk if saying no I wont ever would feel honest? Not that I have intentions or want to, but Ive found I'm so hurt from her being disrespectful of our og agreements and dishonest around what happened between the two of them that the petty side of me wants to pursue it. Realistically I highly doubt I'd ever have sex with them still. Regardless, Shane has decided this hypothetical hookup situation and my response shows I dont care about her or see her as a real friend, and is threatening to end our friendship for suggesting I might sleep with them someday. So with this I turn to the judgemental assholes of the internet - WIBTA for hooking up with this couple after my ex/current friend did and got burned by them?