What are the motifs in The Diamond Mine by Willa Cather?

Family relations are a recurring idea. Cressida's success has not come easily, even though she does have a lot of spirit. "Everything but her driving power Cressida had to get from the outside," says the narrator, when describing how the singer started her career. She has had to work hard to make it in a tough industry, and she has received very little support from her family in the process. In fact, all of the family members expect Cressida to support them.