Interesting!!

Guessing it will be related to their parents and the latest spoiler says that the past will be the reason for Khushi to leave. For Khushi her parents are everything and cannot bear anyone even talking about them in an insulting way. We saw raw anger in Khushi's eyes when Arnav asks her how can she meet the eyes of her parents being the way she is. She warns him not to go there. I suppose their interlinked parents past will be the reason for the huge rift in the future and Khushi will leave as she cannot bear any slur on her parents name!!