Good Posture (2019)

After breaking up with her boyfriend, Lillian moves in with married couple Julia and Don only to overhear them arguing in the night. The front door slams as Don moves out, and the following days sees Lillian, selfish and irresponsible, having to earn her keep by cooking for Julia, a reclusive, distrustful writer who rarely emerges from her room. Though communicating largely through notes, the odd couple gradually forge a bond and help one another to negotiate the foibles, phobias and obstacles that have long hindered their happiness.

Source: TMDb