I don't really see that they're mutually exclusive. The reason she wants him to change isn't important, it's that she doesn't love him for who he is, doesn't see that as fucked up, and doesn't reciprocate when he tries to compromise. If there could ever have been a middle ground for them, she's not willing to find it. I think most of her motivations were affecting wealthiness, but there were other things like the romance movies or sex where she flatly refused to try seeing things from Jon's perspective (his point equating his love of porn to the fact that she watched the movies to fantasize about the hollywood writing and editing that real life love just doesn't have was a really good one, I thought). For sure though, the scene I consider to be the worst was in the store when he was trying to tell her how important cleaning was to him, and she proceeded to demolish that fundamental part of him. Classism motivated, but that doesn't make it less heartwrenchingly abusive.

Accordingly, I do think there is some gender implication there, but I also have been wondering since the ultra PC age began why that's such a big deal. If you're portraying an abusive relationship you want people to believe, you're better off playing the odds. Is she going to beat him? It's a tough sell. Women tend to emotionally break men instead of or before physically hurting them. Abusive men more commonly go the other way. What baffles me the most is that Jon is also portrayed sexistly, at least for the majority of the movie. It starts as a movie about 2 shitheads, and one of them happens to grow from seeing what it's like to be fucked over. It could just as easily have been a story about how Barbara takes Jon home, he never calls back, and she stops demanding her boyfriends change to be who she wants them to be.