Half Broke Horses by Jeanette Walls

Jeannette Walls was raised in poverty and hardship by eccentrically idealistic and unfit parents. If you read The Glass Castle you probably wondered: 
How did these characters come to exist in America, in the 1960s and ’70s? Why did they not settle down and raise their family? It baffled me.
In her new book, Half Broke Horses, Ms. Walls introduces Lily Casey Smith, her maternal grand­mother in a novelistic re-creation of her colorful, hard scrabble life. Lily lived in the first half of the 20th century, and raised a family during the Depression. Reading about the hardships she endured gives a partial answer to that question. 
Lily Casey was born in a one-room mud dugout in West Texas, on the banks of Salt Draw River; At age 5, she helped her father train carriage-horse teams and, once a week, drove to the nearby town to sell eggs. 
Floods and tornadoes flooded the dugout and forced the Caseys to move to a ranch in New Mexico. Lily's father had physical and vocal impairments, so it was Lily, at age 11, who hired and fired laborers and oversaw the workers on the ranch. Her fragile mother was unfit for this hard life.
At 13, Lily was permitted to leave the ranch and go to school in Santa Fe, where she thrived, but after her father squandered her tuition money, she had to leave midway through the 2nd term. 
At 15, Lily took a job at a lonely prairie school. With only a pistol for protection, she left home and traveled over 600 miles to the school house where she lived and worked. Lily was hired on a recommendation from one of her Santa Fe schoolteachers and because certified lady teachers had left their teaching positions for factory jobs. The men were overseas fighting the First World War.
Teaching was her calling and for four years, she taught, but after the war, the seasoned teachers returned and she had to go back home.
For a short time she lived in Chicago where she worked as a maid, but didn't stay long and once again Lily returned home to start again.
In Red Lake she found herself teaching school, and in the evenings she moonlighted racing horses. At one such horse race, her horse got spooked and threw her, which "threw her into the path" of Jim Smith, who would become Jeannette Walls’s grandfather. It was right before the start of Great Depression. 
I “read” the book in audiobook form with Ms. Walls own voice reading the story. I heartily recommend it.