Best friend with homophobic boyfriend

First post here, but I’ll just get into it. My best friend, who I’ve been close to since middle school has been dating a homophobic asshole for the past year. It’s weird because he accepts her bisexuality because he sees it as “hot,” but he hates male gays and refuses to meet me. Not really sure what to do because I feel like my empathy up until this point is just turning into frustration. She openly disagrees with his views, but I feel like the fact that she’s willing to stay with him says a lot about her as a person. This is only one of his many flaws, but since it’s the one that impacts me it’s the one I usually point to. Should I just stop being friends with her? It would be hard, but I would live. Cannot keep listening to her rant about him constantly. What do y’all think?