Some thoughts:
1. Sharon is awesome.
2. I think that the degree of misfortune a person experiences (as in degrees from normal) is pretty significant, so in Will's case, even though he leads a charmed life, the crises that he deals with are pretty intense compared to his normal existence.
3. My intention is not to show Claire as a person who has suddenly become evil (she hasn't), or to have her seem completely out of character by suddenly becoming this uncaring bitch. Ponder your own lives, and how you may get locked into a pattern, or a group, or whatever, and it becomes the norm. That's what I think is happening with Claire. She's been immersed in the elite world of Palo Alto and has become part of it. In a sense, she has lost some of herself to it.