Divorce

I am married since 1 year 7 months. I have a baby of 3 months. I live with my parents and my wife and daughter.My marriage was arranged and it was a grand wedding ceremony. I would like to give divorce to my wife because it seems she is a psyco. Though I donot have any prove for it. She is very much demanding. Sometimes she has problem with me if I talk with my parents, she has endless complains about my parents and my other brothers. I know my family very well. They are very much kind and supporting to her. She has all the comfort required to lead a comfortable life, but still she has endless demsnd. Sometimes an audi,sometimes gold bangles etc etc. As soon as I enter home after long day's hectic work she starts her complains about my mother and father. She finds problem in every solution. If I say her something which is against her, she will start crying like anything. Hit her head against the wall. One day she was shouting at our daughter like anything because baby was crying and she needed a pic for her facebook. There are many more such incidents. She is a housewife and has done interior designing course after graduation.She is from a upper middle class family. It was an arranged marriage. I knew she was difficult to be handled but I thought I could manage. But then things turned out to be just the opposite. It seems I am living in a hell. Our baby was unplanned. Didn't expect to have a baby so soon. Then I thought after the birth of our baby, she will change. But no. Things are becoming worse day by day. Please help me. How shall I proceed with the divorce process? How will my baby and other family members affected? How much do I have to pay for alimony?