Okay, I agree that Kasturi misunderstood Robbie and blamed him for killing Raunak, but everyone makes mistakes. She's already regretted and has had to suffer a lot because of that. I don't think Kasturi did anything wrong by marrying Kabir. I know she has lost her parents because of that, but if she hadn't married Kabir, Kabir and Maasi would never DIE. Robbie and his family would be on the streets, and Kasturi would have to listen to Devika's nonsense for the rest of her life. Aren't things much better now? Just think about it.
And... regarding Kasturi marrying Robbie again, I think we should give her time. After being deceived by Raunak and now being Kabir's widow, we need to give her time. She's human, after all! And there's nothing wrong with Kasturi crying for Kabir... coz she had married him... He was her husband, and taking care of him and his family was her responsibility. She had also spent some good times with him. Kabir wasn't evil from before... He became like that because the lady he had loved left him...