What are the motifs in The Constant Princess by Philippa Gregory?

Selfishness is a recurring idea. There is no doubt that many of the characters in this novel have become accustomed to having whatever they want from life. It's the Spanish ambassador who says that Catalina complained bitterly about the weather during the voyage to England, as if he or someone else would do something to change the conditions so that the young princess would be comfortable and happy. Though Catalina changes dramatically over the course of the next few months, she continues to be selfish is many ways. When given the opportunity to become queen, she refuses because she wants nothing less than to have her son next in line for the throne.