One of the songs I'm obsessed with right now is Dollhouse by Melanie Martinez. It describes a family who use a mask of perfection to hide its flaws and internal conflicts which is a good description of the d'Aubries. Edmond and Mathilde appear to be a perfect high society couple but Edmond tries to seduce her cousin right when they get back from their honeymoon. Marianne appears to a sweet and proper girl but is seeing a petty criminal. When Marianne tells Catharine about how Edmond tried to seduce her, Catharine changes the subject. Catharine and Mimi are upset with Marianne for seeing someone like Augustin behind their backs but Mimi's main concern is the perfect tea party she planned.
Much of this section of the screenplay is Augustin and Marianne trying to communicate during their separation. The song I chose for this section is I Miss You by Blink 182. It has two voices and one can image its two people who are separated singing to each other. Mark Hoppus (the lower voice) could be Augustin singing about how Marianne is his angel and is the only light in his dark situation. Tom DeLonge (the higher voice) could be Marianne singing about how their separation is tormenting her.