Sai is so disturbed by the coffee meet, the hand holding and is not even able to stop herself from bringing it. Why?
She is fighting with him because she has never imagined he would do that. She thinks he might have feelings for Pakhi but wouldn’t have imagined them to be this close that they will hold hands so comfortably. That is why she keeps bringing it up.
“Aapke dil mein Pakhi Didi hain”, “aap apne dil mein dabake rakhthe hain”, she says these so often which shows that she has been thinking it all to be his wish but really never expected him to show it out by meeting her outside the house, in a cafe and also by letting himself to hold her hands to comfort her. She has thought that he has always buried his feelings in his heart, never imagined it would be shown by him this way.
She has never imagined or thought that they could be physically close in some way. She has always thought that he is a guy with morals and wouldn’t cross his lines/limits but this incident has disturbed her. She is not able to accept that Virat would do it since this means that they can be this close too and she is not even able to imagine it.
That is why she is making a big deal about it from my understanding.
To her, this meet is like Virat has finally accepted that he too has feelings for Pakhi. This all has happened only after Samrat returned. So she has assumed that after Samrat had returned, Virat couldn’t even control whatever he has kept buried within him so long and he met Pakhi outside the house. It is as if this time he couldn’t even stop himself from comforting her by holding her hands which she has never seen him doing before or never imagined he would ever do. It is as if Virat had finally brought out his feelings without stopping himself. That is how Sai perceive it as and that is why it is bothering her so much that she keeps bringing it often.