I really liked this movie, but I admit the last ten minutes of the storyline is silly. That being said I think this movie is well worth watching for the acting, not only by the main character who is superb, but almost every one of the supporting cast.
I have seen reviews where there are complains of the extraneous side stories: the mother of a kidnapped child, the doctor with the wife in coma, the brother who can no longer be loved. I think those reviewers have rather missed the point. Most of the movie is a study in loss, and how different people cope, and how profoundly loss of a loved one effects your whole life and mind. At the end it is also how that loss can give you compassion and strength.
Being a Hong Kong "horror" movie, at the end they had to throw in a bit of supernatural connections which is where all logic goes for a hike but the main thrust of the story is very good indeed and the acting is well worth watching.