When the Lilacs Bloom(2010)

Original title: Когда цветет сирень

The main heroine lives in a tiny apartment with her elderly mother and young son. To support her family, she has to work hard, leaving her with almost no time for a personal life. Her friend, a housekeeper in a wealthy family, invites her to a gathering at her fiancé’s friends’ place, hoping to cheer her up a little.