Sympathy for Ellen. . .at first . . .spoilers

I've just seen this film. Although it is obvious that she is manipulative enough to wrangle a marriage out of Richard, and callous enough to leave her previous fiance behind, I found myself sympathizing with her for the first half of the film.

Richard does some really stupid stuff as a new husband. I would imagine that any new bride would want some alone time with her man, somehow, he doesn't get that. He keeps inviting more and more people. . .crazy. They never did get a chance to connect. He spends a lot more alone time with Ruth, not good. Any wife would be jealous of that relationship. Of course, a non psychopathic woman would first tell him how it makes her feel, and then threaten to leave, and then do so if things didn't change. Ellen just sees fit to murder those that take his time, which backfires and makes things worse for her. Her last act is utterly unbelievable, a sacrifice to ruin her sister. Totally insane.

I do wonder how this movie would be different if remade. We have a lot more insight into psychopathic personalities now. I wonder if we would get a different performance.