<human>: Say, for instance, you know a girl (27f) who has a tendency to wreck relationships and go after married/engaged/already committed men. Say a mutual friend of yours likes posts and pictures of her in a relationship with a married man (30s m), and also see pictures and statuses of said man and his wife (30s f). His wife appears to have no clue that her husband is also in a relationship. 

Should I say anything? I've been in the wife's shoes, and I would have wanted someone to step up for me. On the other hand, it's really none of my business, and maybe they have some sort of polygamist relationship going on?

Can you condense the text into three sentences or less?
<bot>: someone who I know to be a "poacher" is pursuing a relationship with a married man. His wife seems to be completely oblivious, should I say anything?