EDIT: So, yeah, decided to walk away from the situation entirely.
Hey, Bombers. Got a bit of a situation, and I don't really want to bring it up with people I know personally (don't need word of mouth getting involved).
Here's the situation: My friend - let's call her Jill for this - has been hanging out with this guy - we'll call him Bob. Bob is engaged to another woman - we can call her Mary. Jill has done questionable things with guys who are in committed relationships in the past, so the concern is that Jill and Bob are fooling around behind Mary's back.
Other than Jill's past offenses with this, she has been acting peculiar whenever prompted about Bob. She has said things like "there are things in my life going on that I could never tell you," which makes me think she's hiding something because I was so disapproving of her actions when she slept with a guy who had a girlfriend in the past. During a conversation about Bob, when I asked if there was something going on, she said she didn't want to talk about it but "there's more to the story." Perhaps the most damning evidence though, is that when I asked if Mary cared about her and Bob hanging out together alone while Mary wasn't there Jill responded, "she's usually MIA." To me, that response implies that Mary isn't even aware that Jill and Bob are hanging out. Also, a quick Facebook search showed me that Jill and Mary aren't friends, perhaps more evidence that Mary isn't aware of her. I know that if I were friends with an engaged woman, I'd certainly befriend her fiance so that he'd be comfortable with the situation.
Here's my dilemma, do I contact Mary and inform her, or is that crossing the line? I've thought about this a bit. It seems best not to jump to conclusions, but at the same time what could it hurt to just ask her if she's aware of the situation? I have considered messaging her anonymously and just checking in.
What do you guys think?
Oh, and does this qualify for the girl trouble picture?