Perris, California by Rachel Stark

In this unforgettable debut novel, twenty-seven-year-old Tessa, pregnant with her third child and living in a trailer on her mother-in-law's property, encounters the woman she used to love—leading Tessa to question the very foundations of the life she's built
Abandoned first by her father and then her mother, as a girl Tessa is left to live with her abusive stepfather and stepbrother. She survives by finding reserves of strength in herself, and by the surprising, transformative love of another teenage girl, Mel, who sees through Tessa's tough exterior to the vulnerable, scarred, loving woman inside. When she suddenly loses Mel, too, Tessa stumbles into a saving grace of a different kind with Henry and his mama, Angie, becoming a mother and finding herself in a familial existence that somehow carries her into adulthood—until the day she runs into Mel, who has just returned to Perris after years away.
Filled with violence, tragedy, tenderness, longing, and the unvarnished courage of women living in a mostly unseen America, Perris, California is the utterly gripping story of Tessa's journey from trauma to healing, and it introduces us to one of the most indelible female characters since Bone Boatwright in Dorothy Allison's Bastard Out of Carolina or Ruth Langmore in Ozark.