Unfortunately, this reminds me of a situation a friend of mine told me about a few years ago.
Donna and Brenda were very good friends and would "hang out" and talk often, in addition, they worked together (I'm not sure if they worked the same shift).
Donna was living with her boyfriend possibly for a few years and eventually things went sour and she "kicked" him out of her apartment (I am pretty sure that she told her good friend about their "break up").
Normally, I would think that the boyfriend would become "persona non grata" with her female friends and family, but this apparently was not the case.
You see, Brenda allowed the ex-boyfriend of her good friend Donna to move in and live with her, but never told Donna about her new living arrangements.
PS. I actually know Brenda, who in my opinion was always a sweet, quiet and innocent young lady (at least that was how I saw her and how she was whenever I interacted with her).