Ugh... 😔

I know by posting this I might get mean/rude comments but I hope y’all understand where I’m coming from. My brother who’s 18 broke up with his girlfriend about a year ago but her and I are good friends. Before asking her to be one of my bridesmaids I asked my brother if he’d be okay with it and he was mature and said whatever makes me happy so I thought great. Well now she’s dating another guy and I realized that she and my brother stopped following each other on social media... my brother is not one to talk about his feelings and I know if I ask him anything he will say he doesn’t care but I have a feeling he is hurt... and now I’m regretting asking her to be one of my bridesmaids.. would it be such a bitch move to explain all this to her and tell her why I don’t want her to be in the wedding? I would do all this in the best respectful way possible. I know it sounds horrible but technically she hasn’t even said yes to being one of my bridesmaids.. please don’t be mean about it. I understand it can be such a mean thing to do. 😔