It feels like this was supposed to be a spoof of something, but I'm not sure what. Maybe a spoof of cheesy French romance movies? It works but I think a lack of foreshadowing made the end feel abrupt. But it was also over the top rediculous in a good way.
I think the other reviews here are too harsh. Perhaps a lot of people watch this not expecting it to be a satire. It does have a serious tone so it doesn't immediately come off as a satirical, and that was a missed opportunity in the editing. It still worked well. The point of this movie is basically just that everyone seems crazy at first but they're just normal people with a few quirks that make the situation seem much worse than it is. The point is that things were never as crazy as they seemed.
I think the other reviews here are too harsh. Perhaps a lot of people watch this not expecting it to be a satire. It does have a serious tone so it doesn't immediately come off as a satirical, and that was a missed opportunity in the editing. It still worked well. The point of this movie is basically just that everyone seems crazy at first but they're just normal people with a few quirks that make the situation seem much worse than it is. The point is that things were never as crazy as they seemed.