I know many of us are disappointed with how evil Shaurya has turned out to be. I am going to base my case on this line itself, he is acting too evil. I know this blackmail hypothesis was discussed a lot during the wedding.But just like Mehek I feel Shaurya is not that evil that despite knowing PD's condition he would act in such a way. As we all know he does have some feelings for Mehek but he treats her worse than an enemy, I mean he would have listened to even Svetlana or mamma if they had begged to him like this. He definitely had feelings of guilt and sadness in his eyes when he saw Mehek begging. There must be some reason, maybe some enemy or mama is blackmailing him, they always wanted Mehek and Shaurya to be away from each other, so that Shaurya's restaurant does not succeed. Perhaps someone set the blackmail condition that you should get Mehek to leave you or I will... This might have resulted in Shaurya acting like a villain.
PS:- if he is in acting like this on his own, he is definitely a jerk.