Nice, melancholy driven movie, however not for everyone. It's slow, actually very slow, which does not mean bad. There are many amazing "slow" directors in this world. Jim Jarmusch is very slow, Andrei Tarkovsky was extremely slow but both are amazing masters. If you are person who can not survive another 10 minutes without checking on your smartphone or like action films / romantic comedy films / horror films - "Bittersweet Monday" is not for you. There is not much story, but you will feel like you are prying into someone's private life. This movie is very moody and melancholic, you need to relax to feel it. It's more like contemplation or meditation, rather than entertainment. Whisper, but not scream.
Actors are very appealing and look like real people, not a plastic pop starts. Minus star for an average cinematography (it's very low budget film, but really needs better approach here). Music is very pleasant and fits extremely well.