AITAH for hiding that my best friend’s ex has no intention of ever getting back together w/ her?

My best friend (29) and her boyfriend (30) of 10 years broke up 6 months ago. The breakup has been slow, they’ve tried therapy and they had been having a hard time cutting things off partly, I think, because our friend group is so intertwined. We’re essentially all married/ long term couples who have known each other since college.

My husband is one of his best friends, I’m one her best friends. Naturally we all talk about this breakup. She says they’re working on things, but he tells my husband they’re broken up for good, that he told her this and she still wants to hang out. I’m starting to feel like a really bad friend since it seems she is much more into the idea of fixing the relationship than he is. I feel guilty for knowing what he says behind her back, but at the same time telling her anything is selling out my husband. It might be my best friend bias, but I have a feeling he’s never told her he doesn’t see them ever back together as it’s not the first time I’ve seen him lie. (For example, she was upset he wasn’t returning her calls the other day and he said his brother was over, meanwhile his brother was out at a company holiday party.) AITAH?