Does mourning have a use-by date... like yogurts? And what exactly does the term "mourning" mean?

Set in a scorching Brussels, Babel Opera blends documentary and fiction during the intense rehearsals of Mozart’s Don Giovanni. As an international cast struggles to bring the opera to life, four fictional characters appear around the set. Their real-life conflicts, infidelities, and passions begin to mirror the seductions of the opera itself, completely blurring the lines between art and reality as the grand premiere approaches.