Thank God this is only a show n so we can totally forgive the writers who have made Radhika behave like a brainless donkey whose only motive is to keep her inlaws happy n save her marriage even if her husband is bedding another woman.
The actual motive of an affair has been totally circumvented to keep up the moral standards of the serial.
But in reality if you want to show a woman with even an iota of common sense, she'd hv taken the help of the law at the first instance itself coz a man who puts his wife as a second preference isn't worth being given the honour of being married in the first place.
All said n done it still ain't too late n the serial can still save face by making sure that the divorce does happen n Radhika wins a good chunk of alimony ..even if that blind-as-a-bat-dumb mother in law dies