So i am getting right into the point :
I feel like the stalker has always been VIDYUT!
We know how sleazy he was always. It cant be that it began all of a sudden. It must have been like that from before. Vidyut saw sharanya because of Vyom and his obsession started. Which is why Sharanya complained to Rajan.
Rajan might have been against ShiVom because of "status" issue.
Now coming to Rajan and MAdhvi,
Clearly, MAdhvi was manupulated into marrying Rajan which she now regrets. There was this one episode where she said that the father son duo are the same, they only know how to force.
Now I feel like, in some way or the other, Shiv is related to the Bedis.
Either rajan's brother's illegitimate son or MAdhvi's illegitimate son.
It seems MAdhvi was close to Shiv because she came and giftem him that guitar. She couldve just threatened him to leave Sharanaya or just scold him but she was being nice to him, pleading him. It either could be Shiv was related and she knew or because Vyom and Shiv grew up together somehow and she adored him. Either way, its obvious that MAdhvi had a special spot for him.
But Shiv's background story of being an orphan and surviving 3 days in the ice must have some significance for the future.