I read a book in the late nineties or early two thousands about a woman who makes an unexpected trip to California with her daughter to visit her estranged sister (I think she may have found out her husband was having an affair, but can’t quite remember).

The teenage daughter had suffered from anorexia in the past, the sister was a failed actress. The daughter does a screen test for a movie about Joan of Arc while they’re in Hollywood. The three of them stay in someone’s fancy house in a wooded area (the Redwoods maybe) and the mother has an affair with the caretaker, whose life motto is Carpe Diem and who lives in an old fire tower.

At the beginning of the book the main character describes trapping rats in/near her house and releasing them in the creek behind the house, and then swimming in the creek with the rats. She also describes getting ready for a party (a work function for her husband?) and not having time to wash her hair after the swim in the creek, so she just slicked her hair back, went without makeup (she describes her coppery freckles), bright red lipstick, and a flower behind her ear.