It was a very good idea for a film. But in practice, and I suppose watching it for the first time in the present day, in a way it felt a bit melodramatic. "Ahh! My life is a lie! Everyone is in on it! I have to escape!"
His entire life is literally a lie. His parents, his wife and his best friend have been lying to him every minute of his existence. How else did you expect him to act?
I do agree that walking into a movie knowing nothing is the best way to watch a film, though