I haven't watched the episode. Have not been able to make myself watch it completely for 2 weeks. Either its utter crap or too emotional to bear.
But I watched the precap and what a lot of guessed during the breakup episode is pretty much right. Sai had assumed that Virat was saying it all in anger as he tends to go overboard when he is upset. She was expecting them to be just words and things would go back to normal. But with the transfer and his aloofness it has suddenly dawned on her that he may be serious and he might go away from her. Its the beginning of that uneasiness towards realisation