In all these years, there has not been any person before whom virat could break down and actually express how bad he was feeling.
Nobody who could provide the selfless warmth that sai provided. No one, before whom he could cry and talk about sai endlessly and someone who will be his true support and a non judgemental person who'd understand him and listen to him quietly.
Ninash anniversary and samrat death (remember the way virat used to just lean on her and sai used to provide her that warmth and affection).
He could weep like a baby in front of her and she would provide him that affection that he required.
They both bring out the best and worst of each other.
So, when he saw her, his pain and hurt resulted in anger. The pain which we show only before that one person. That he needed her, her shoulder to cry on. He needed her during weak times and to cry and shout. He needed the person due to whom he was feeling the most hurt and he was so helpless to get that person, so when he saw her standing before him, all the pain and hurt resulted in anger causing him to leave before he could made a mess.
That anger is a way of showing her his pain. That he does only with sai.
We're not able to connect with the Anger cause they didn't show him grieving properly, slowly. Begging for sai's breaths.
That's why we've to understand it through our own understanding.
But, that anger were his hidden emotions of helplessness throughout all these years, and that he kept blaming himself but she was alive. And, she didn't love him enough to return and kept living easily without him, while he was dying bit by bit. (Even though the situation is same with sai, but he isn't aware yet).
So, it was more of pain than anger, I'd say.
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