I have a group of girlfriends. One of them, Karen, stopped talking to me a few years ago after I introduced her to a man who ended up being her fiance. She also asked him to stop speaking to me. As best as I can tell, she was uncomfortable with the fact that he and I were friends before they met (he and I never dated and there wasn't any movement in that direction). There was no fight, no confrontation, nothing. For reasons unrelated to me, they ended up not getting married.
Now, my other girlfriends probably know more about this story than I do because she talks to them and they still hang out with Karen and will exclude me when she's going to be there. Two of them just cancelled plans to see a movie tomorrow (tickets bought, everything) because Karen's unexpectedly in town that that's the only time they'll be able to get together.
I don't know what I expect from them but is it too much to ask that they would tell Karen that she's being shitty and they would stop being complicit in this?