A light bulb went into my head after watching the precap today and hence decided to come over to this thread. Please ignore if this has already been discussed.
OK this is my final opinion and I am not going to change it.
The precap had me confused. RK's anguished look makes me believe that what he did was NOT A REVENGE, it was more like he committed HARAKIRI.
RK's POV
No one can separate you from me other than me. Not even GOD has the power to do it. I just won't allow it. I love you just way too much. The whole Ballu saga where I saw Madhu hanging from that rope shook me up to the core. I felt helpless in that situation. It was beyond my control. It brought back the painful memories of my father's suicide by hanging. That is when it hit me that I love her just so much that it is now up to me to take control and decide that such siutation never comes up again where I may be faced with the possibility of losing Madhu for good. So why not cut her lose myself right now before such situation ever comes up. But how? Madhu is so big hearted that she has forgiven me for all my sins however big or small. So what must I do to make her hate me, loath me in her mind? Oh I know !! She is so keen on completing the remaining 3 pheras. and start a new life with me. Let me take advantage of that, make a mockery of this marriage again, disgrace her in public. That will definitely drive her away from me. Then I will be the one who has set her free on my terms and no one can snatch her away from me without my consent.
This is the STUPIDEST theory if true. It is like saying I don't want to go on living because I know one day I am going to die. Just like the love confession, once again he has taken the preemptive action in this case.