Wife had affair

Hi Iam a muslim and i got married in the year 2005.I have 2 kids. we were happy for nearly 4 years after marriage and latter my wife started Quarreling often for no reasons and i was always in the dark and was not able to understand the reason. in the year 2011 i was surprised to know that she was in affair with a boy and i brought this to the notice of my wife parents and brothers they convinced us both and made us to stay with each other. But my wife was not happy to stay with me and she was playing a double role as if she has forget every thing and when ever she is with there parents she tells that iam torturing telling the past but i did not do so again when she comes to me she quarreled for silly silly reasons and will not at all get convinced. Now her father passed away but due to the false complains against me to there mother and brother they have started torturing telling that they will go to file a case against me on dowry, torture in house and so on. iam worried i will live life if she is with me to avoid hazzle but she is creating a scene unnecessary please advice.