What the Hell was this movie about?

I feel like this is the kind of movie that should have affected me to my core, because its substance is more than what meets the eye. But, for the life of me, I can't figure out what that "more" is.

Here's what I've been able to put together so far:

1. There's serious risk inherent in relationships built on superficial bases and "blind" love.

That's it. But, it still doesn't explain the chronological hodgepodge that was the last 30 minutes or so (or maybe it does and I don't see it?). It also doesn't take his "widower" status into account. Does the message involve a warning about moving on after the untimely end of a first marriage? I don't see any stigma surrounding that behavior in the West (certainly not in the States), but maybe such a stigma exists in Japan?

The lead actress and director both indicated that it should make men fear women. That made me think of Teeth. But, Aoyama seemed like a good guy, so it didn't seem like "just punishment" was part of this movie's message. Another thing that occurred to me is that it might warn us that people's most serious and destructive issues lie so far beneath their surfaces that audition-style socializing (using superficial or shallow personal cues to form the basis of "love") couldn't possibly reveal them.

Please, somebody respond with their take on what this movie was about. It can't just be about an unlucky guy who gets tortured by a psycho with a rocky past.