Who is Clara from Lonesome Dove and what is their importance?

Clara is the love of Gus's life. She lives on the Platte with her husband Bob, their two girls Sally and Betsey, and Cholo, their ranch hand. Hospitable and capable, Clara is a woman of strength and character. Having lost three sons to illness, she is nevertheless strong and decisive. When her husband is kicked by a horse, she takes over the running of the ranch, doing an even better job than he did. She loves Gus, but his rambling and unsettled life is not the life she wants, and she tells him so many times.