I reckon that, because maasi can 'feel jhanki' she will claim that 'jhanki's' soul/spirit is in her and that she wants her love; shekar back. I think thats her ultimate motive, because she is trying to take shomi's place. Notice her, when shomi and shekar have their moments, and when Shekar shouts at her. Because first she went to MM with shekar and swara instead of shomi, traditionally being the mother and father attending for such Occassion. Thus staining her saree. Secondly she took Shomi's seat when the Maheswari's were invited. Therefore she is using ragini as her pawn to get there, getting her all emotional an all that. Thats why she doesn't want swaragini to reunite, because she knows Swara will go through anything to maintain her parents relationship as she has previously. I don't think shes behind the seperation of swasan.
Maybe Sanskar is right, maybe it is Kavita because her entry was short lived. Perhaps to keep her character they will show her behind all this. Unless you guys know of otherwise that she only enrolled for a small part?