Malos hábitos (2007) on Netflix

Plot summary

Matilde gives up her medical studies to enter a convent, certain a second great flood will come. She starves herself in secret, believing her hunger can hold it back, and she is preparing her cousin Linda for her first communion. Linda's mother Elena is thin and ashamed of her daughter's weight; she puts the girl on strict diets and exercise so Linda will look like a princess at the communion, and Linda hides snacks in her room to eat alone. Gustavo, Elena's husband and Matilde's brother, can no longer bear his wife's fixation on appearance, and he turns to a student known as Gordibuena, who loves food and is at ease with how she looks.