Bitter fact is, once marriage has taken place, according to rituals in presence of a registrar or parents and huge number of relatives and friends, its over.
Untying the knot will take a long time according to law.
Intervention of elders for untying the knot on their own does not hold any value in the eyes of law.
Many a marriage take place hiding certain negative points and mistakes. But in law there are written points as to on which ground divorce will be granted.
Keeping a eye on the recent bill passed which totally favors woman, I suggest you to follow Adv Rama Chary's advice, as other people who are facing divorce petition etc have suggested video recording etc wont be any use. There should be a longstanding impairment of function of the brain, which is totally unhandlable by the husband, then you can seek divorce, or else any such attempt will be futile.
Further, I would suggest to speak to her parents which are your in-laws on this regard and try to find a solution with regard to her behavior.
During 92 I had seen such a case, where girl used to behave like a robot after marriage, driving the husband nuts, on closer inspection it was found that the girl was in love with someone else and the cause of her robotic behavior was none else than her parents forcing her into this marriage. So, try to check about her background, its still not late.
