1) Abhimanyu didn't seek out Abhinav to show him attitude or his anger. Abhimanyu is minding his own business and Abhinav kept badgering him asking him to talk to him, when Abhimanyu started to walk away, Abhinav held his hand and tried to stop him, again Abhimanyu shirked his hand away.
Abhinav's reasoning was that Abhimanyu will be mad at him or yell at him or hit him but he'll speak to him
Abhinav, here, is not expecting a "Dola re dola" brotherly dance sequence with Abhimanyu, he is well aware of Abhimanyu's state of mind
2) Abhimanyu got to know that he has a son, he was Abhinav's friend, doesn't mean the friendship will remain the same after disclosure of a big information like this one. It was Akshara's information to share, sure
Similarly, It is Abhimanyu's prerogative whether he wishes to remain friends with Abhinav or not, you can't force people to talk to you or be friends with you.
Abhimanyu's word - I had an accident, could have died without knowing that I have a son
He is angry that these two chose to withheld this information even in life and death situation.
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