Perhaps, Rads might have lost her memory. Or she might not have.
If she hasn't lost her memory, she won't take a minute to forgive Dev... whatever the sins he might have done towards her, such is Radhika's generosity. She would even forgive the entire PF!
After Barkha is punished aptly, they could show this. Now where she is, is still a mystery. Perhaps she has been taken in to shelter by some people who are good. Or she might be unconscious and would remember everything once the sinners are punished...with kanha's powers, she might get to know automatically what happened in Purohit House... when Kanha had taken her form (this could be Kanha's magic) So for the people of Purohit Bhavan, Radhika could have been always there! I mean the moment Kanha decides to leave PF, Rads might come and everyone would think it was Rads with them always.
Or else, they could start RaDev story again, this can happen if she loses her memory and Dev goes back to start afresh their romance. Remember he said in the previous episode that they have never got to know each other much. Its true...since the time they met, they have been embroiled in various issues -- from Rohan to DDjee to Barkha! This hardly gave them any time to know each other. Although they loved each other...the understanding was perhaps less because they never sat down and shared a few talks! Even during the kidnapping scenario, they were always in a fear of being found out! (well, that scene of Dev telling Rads "We didn't get to know each other pre and post marriage...could also be a way for writers to justify Dev's mistrust on Radhika!!) Dunno...but lets see :))