This is weird.. how does the brother feel about seeing her? It would be one thing if he broke things off and she didn't want to see him, that's understandable... but she broke it off and she is acting like that? Maybe she's more embarrassed by the break up? Maybe she's uncomfortable about something? I say keep doing what you're doing... it's her loss if she doesn't want to hook up on those occasions... let the brother know what the situation is if you haven't already, just be up front and let her know that whatever happened with her and this brother is between them and you and your boyfriend are still friends with him. I dunno... I look forward to the day my ex-wife is reinstated so I can be friends with her again... no romance or anything like that with her, but maybe I'm strange for feeling that way...