FH had a friend for 10 years, "A". He's a very condescending and aggressive, but smart guy. I wasn't his biggest fan, but I sucked it up for FH. Last June, we went on vacation with him, his wife "B", and FH's brother. It went so badly, we left early and it ended their friendship. We haven't talked to him since. A month or so ago, we realized that something happened between A and B and were led to believe she left him.
B is the sweetest girl, and FH and I both love her. She reached out to us a month ago to give belated congratulations and confirmed that she left A for good. We decided to invite her over last night.
We knew her relationship was not the best, but we had no idea how bad. A and B had a third member of their relationship that we knew about, "C". C was initially supposed to be a fun fling, but quickly became a part of their relationship. C is also an alcoholic and very dependent on A. Eventually, A and C began dating behind B's back. (cont.)