Arnav Singh Raizada is going to erupt in volcanic proportions because the thing he fears the most is death. Not for himself but the death of his loved ones. He will freak out because his mother had committed suicide. He is the way he is because of that. When he finds out Khushi is going to attempt suicide for whatever reason, he will flip out in every sense of the word.
To get him to open his mouth you need to get into the belly of the beast. The only way that can consume ASR's brotherly instinct is if you awaken Arnav and ASR's fear of the death of his loved one and that loved one is Khushi.I think that's why they are showing the suicide sequence. To push Arnav Singh Raizada to the stage where he has no choice but erupt and blurt everything out.
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