How is the relationship between Amir and Hassan emphasized in chapter 8?

Chapter 8 addresses some of the immediate aftereffects of Hassan's attack. Although Hassan is still completing his daily chores, Amir barely sees him. When Ali questions Amir, Amir lies to him, asking, "how should I know what's wrong with him?" This chapter is all about how Amir's relationship with Hassan is forever changed because of the rape incident. Indeed Amir's relationship with himself is forever changed. As they drove along in the car, one friend's twin daughters recounted Amir's victory at the kite-fighting tournament. At this, Amir's carsickness overwhelmed him and he vomited. As they aired out the van on the roadside, Amir saw Hassan's bloodied pants in his head.