When Sin was trying to get Amar to break his marriage with Divya, she "wished" for him that this time around he have better luck in love ...er something like that..i am having a hard time translating " bhagwan kare is baar tumhe tumhare pyaar ka sila zaroor mile"...
that was cryptic. & foreshadowing. but today's precap showed Nani Ma pointing to Divya as killing Sagar. sooooo my thought is that Sin will distort Sagar/Vidya's history to make it seem like Vidya was evil, unfaithful, didnt love sagar, and killed him. Probably in Sin style..where she shouts and everyone believes her.
then any proof divz has of a past life together with amar will be useless. And Samraat can swoop in and be the 'adulterous' party with Divz.