The matter of fact is that you love your wife very deeply and you have impression (might be correct one) that she also loves you and which opinion is not acceptable to the boy's parents as well as girl's parents. I think you are on right track that you love your wife and she also reciprocates to you.
If there is no interference from outside, you both can live happily.
For that, you have to take some unconventional steps:
1. Do not file any RCR case again.
2. Do not develop communicatin gap between you and your wife. Talk to her on mobile and exchage gifts at regular intervals.
3. As your wife is in search of job instead of persuing the complaint filed on behalf of her by her sister and parents in the police station, you meet your wife twice or thrice in a week in the evenings and enjoy the life together. In these meetings, always avoid to talk about your or her parents, sisters etc. Both share happy momements and gradually develop mutual love, confidence and blissfulness, so that there will be, in the near future, a time comes where you both may have to live separately from your and their parents, so that outside interference can be eliminated totally.
4. Now comes the most important question. How to tackle the complaint which may turn into Section 498-A F.I.R. You tell the police that till your wife comes to the police station to pursue the case, there is no purpose for mediation. Once, if she comes, then ask the mediator to send her parents and sister away from the mediation, so that purposeful mediation can happen. If you think, in the present circumstances, it may be difficult to deal with police in such manner, then as suggested by Mr. Shonee go and get Anticipatory Bail. If you are bold enough, and if you do not like the way in which CAW cell police personnel are dealing with you at the behest of parents and sister of the wife, you can go to High Court to get a direction against CAW cell to set its house right and do mediation meaningfully eliminating the external influence.
Wish you best of luck.