I don't agree with what you said. Madhu isn't doing anything wrong so far in her eyes and I think she has the right to do what she is doing.
She was an "angel" at first. Even when RK tortured her emotionally she stood up and got past it. He tried to break her so many times and she still didn't break.
Then his game plan changed, He used one thing that would shatter her and took advantage of that. He made her believe that he was falling in love with her. His own demeanor changed and she "supposedly" saw what was behind all that ego. She changed as well and her being an "angel" she forgave him for what he had done. And sadly she fell in love with him.
But then at that night when they were getting married, he told her of his game plan. She was just his "prey." And that's when she broke completely. How could she look at the man she hopelessly fell in love with and see him tell her that he faked all of it?
Then he wants her back. HELL NO. All he has done is humiliate her, treat her as some toy and scream "MINE, MINE, MINE."
I thought maybe that Holi day if he had admitted to her that he loved her, asked for forgiveness and told her everything that he should then maybe they still had a chance. But no instead he forces her, ties her, and has the nerve to blackmail her too.
Like what in the hell is he doing? And then she agrees to start everything over, all of a sudden. I didn't like that until Madhu told her mother that she was trying to teach him a lesson. That is exactly what he needs.
RK is a kameena and he is proud of it. It would have been amusing if he had a soft spot for her but sometimes it seems that soft spot is only for Deepali. And the most outrageous part is he doesn't even realize what he had put Madhu through. He himself states that all of what he had done with her was just a little fight with his Biwi. And I think thats what set her off on her revenge plan.
And is she entitled to it? Uh YEAH. Is she still an "angel"? She's human. Someone who went through so much emotional torture, healed then shattered in a moments grasp is going to change. She tried to kick him out of her life, forget him and live off as she was doing before him. But what can she do if he's just forcing himslef into her life as if he owns it.
And sadly RK claims he owns that to.
Is she right in what she is doing? In my opinion yes.