He doesn't want to be friends because he feels to guilty for not telling anyone about Hassan getting raped.
The relationship between Amir and Hassan changes from one of strong friendship and loyalty to one marked by betrayal and guilt. Amir's actions lead to a deep fracture in their bond, and he struggles with feelings of shame and regret for the way he treated Hassan. Despite this, their connection remains complex and multifaceted throughout the story.
Because he can't bear to be in the same house as Hassan from the guilt of watching hassan getting raped and not doing anything about it.
Amir threw pomegranates at Hassan out of frustration and jealousy stemming from their complex relationship and his own insecurities about his father's affection for Hassan. This act was an expression of Amir's conflicting emotions and desire to hurt Hassan in the heat of the moment.
Actually, they are half brothers. Amir had found out that when Rahim Khan had hinted that Ali was not Hassan's father but Baba was (which explains why Baba had a closer relationship to Hassan and Amir).
Amir is selfish and Hassan is humble and loyal to Amir. Hassan is a Hazara, Amir is a pashtun. Amir is granted to right to get an education, Hassan is not.
One example of brotherhood in The Kite Runner is the relationship between Amir and Hassan. Despite not being blood-related, they have a close bond of brotherhood and loyalty. Hassan's willingness to sacrifice himself for Amir, and Amir's guilt and redemption for betraying Hassan, highlight the theme of brotherhood in the novel.
Amir feels jealousy towards Hassan when Baba shows favoritism towards Hassan, when Hassan excels at kite running, and when Hassan receives attention and affection from Baba. These instances highlight Amir's deep-seated feelings of inadequacy and envy towards Hassan despite their close relationship.
The pomegranate tree in the backyard of Amir's childhood home in "The Kite Runner" is inscribed with the words "Amir and Hassan, the sultans of Kabul". These words symbolize Amir and Hassan's close friendship and the happier times they shared as children before their lives were changed by betrayal and violence.
Amir dislikes the guilt he carries for betraying his friend Hassan, as well as the strained relationship with his father. He likes writing and briefly enjoying kite flying competitions with Hassan.
Amir steals Hassan's watch in "The Kite Runner" by Khaled Hosseini. This act further complicates their already strained relationship and becomes a source of guilt for Amir.
if he had not seen him come out of his wifes womb himself
Hassan doesn't tell the truth about Amir to protect their relationship and honor. He values their friendship and doesn't want to break the trust between them, even if it means taking the blame for something he didn't do. Hassan's loyalty and selflessness are stronger than his desire to seek justice for himself.
In 'The Kite Flyer,' Amir is afraid to be Hassan's true friend because he has bought into the religious and classicist caste system in Afghanistan. Hassan is from a much lower social caste, and people of this caste are considered to be unworthy. As a result, although he likes Hassan, he doesn't possess the strength of character required to be his friend.
Amir frames Hassan for stealing money and a watch, knowing that Hassan will take the blame to protect him. Amir stands by and does nothing to stop it, thus indirectly getting both Ali and Hassan in trouble.