How are Mariam in A Thousand Splendid Suns and Mary Carson in The Thorn Birds different from each other?

The character of Mariam in A Thousand Splendid Suns is both insecure and misguided. Her mother gave her a negative impression of herself and her ability to succeed in life, and those feelings were subsequently reinforced by others. She is undervalued by an abusive and domineering husband, and her overwhelming sense of discontent leads her to look for happiness outside herself. She believes her baby will make her happy, and when she miscarries, she believes that unhappiness is what she deserves.
Mary Carson in The Thorn Birds, on the other hand, demonstrates a clear sense of entitlement. Whereas Mariam believes she deserves unhappiness, Mary believes she deserves the best of everything and whatever she wants – and she makes it her mission to get it. Mary controls people, whereas Mariam allows herself to be controlled, both by others and by her insecurities. Mary is domineering and aggressive, willing to stop at virtually nothing to achieve her goals. She makes things happen; Mariam, on the other hand, allows things to happen to her. Mary takes action to control the course of her life, albeit in self-serving ways. Mariam resorts to murder when she finally takes action. After a life of abuse and subjugation, she spins out of control.