From reading your comments I realised that the ending was incomplete. Sorry dears .. I guess because of exam pressure these points skipped from my mind. Don't worry I will post an epilogue about the culprit and the Raizadas.

And for Arnav"s punishment it is explained in khushi's words. He left everything for her and never hurt her until then. Then why can't she forgive him when he truly repent it. We all does that. We forgive our dear ones eventhough they hurt us unintentionally.