White Oleander (2002) on Netflix

Astrid Magnussen is a 15 year old girl, living in California. Her mother, Ingrid, is a beautiful, free-spirited poet. Their life, though unusual, is satisfying until one day, a man named Barry Kolker (that her mother refers to at first as "The goat man") comes into their lives, and Ingrid falls madly in love with him, only to have her heart broken, and her life ruined. For revenge, Ingrid murders Barry with the deadly poison of her favourite flower: The White Oleander. She is sent to prison for life, and Astrid has to go through foster home after foster home. Throughout nearly a decade she experiences forbidden love, religion, near-death experiences, drugs, starvation, and how it feels to be loved. But throughout these years, she keeps in touch with her mother via letters to prison. And while Ingrid's gift is to give Astrid the power to survive, Astrid's gift is to teach her Mother about love.