What she said can be interpreted by Arnav as she HAD feelings for her Snake Fiancee! SO when he finds out WHO her Fiancee was, HE thinks that maybe Khushi LOVED his Snake Jija???
OH NO... This is a STRONG possibility! Therefore he thinks if HE marries Khushi, then she will NEVER be able to come between Anji and Shyam again? Maybe THIS is what will propel him to marry her? Coz HE thinks she had feelings for Shyam and Visa-versa, which means SHE may be a threat to Anji's marriage?
This truth MAY come out after the two have already become a couple and this will cause a Rift in their relationship? So will THIS be the "Love will seperate them" phase? OR have we already seen that?? (Since they were seen to be falling in love B4 Diwali, and then things crashed and burned)!!