This sounds a hell of a lot more like an issue with you vs an issue with the term. When I think of 'bro', I think of the short form of calling someone brother endearingly. I wasn't even aware of the frat context until a few years ago. Hell, even within the frat context, it's not necessary "obvnoxious, stupid, despicable, disrespectful", it's just a young guy who's part of the party culture that's associated with college, at least in the US.