In the mood for love, although I've never been in this situation, is the definition of love to me. That glimmer of hope that hey someone understands who you are and you who they are. Not that they're perfect or fall under a certain set of standards but that those involved exist and allow you to exist in your natural journey through life (even in incredible moments of pain, shared or singular). What's sadder: your mate in bed with your neighbor or finding love you can't capitalize on. Being alone in the big city is a common theme in visual mediums but the temporary bond created based on this loneliness may be even worse due to its core in even being let alone it's inability to last. He has the man w no name qualities of Noir, notice how her wardrobe blends into its surroundings when she's around others but stands out w him or in the rain. One of the few love stories that rides it's rhythm to the fullest. Think back to the early question with a new perspective : What's sadder? The hurt we do experience or the desire that we force ourselves not to. The brilliance of this movie is that w the last two scenes he shows how this question applies to us all personally and as a people (in whole).