Divorce

Hi, I'm a Sikh male currently living and working outside of India. My wife is here with me, however she will soon be moving to Mumbai with both my daughters. We have been married for 12 years. However for the past few years we both don't have a very happy married life but we continued as we have 2 daughters and as in India divorce is not very comfortable accepted in families. While I'm working abroad she lived back in India for my daughters schooling and also as she was not interested in living together as our relation was not great for few years. She moved with me in August 2015 but still we had a distance. In December 2015, I fell for a colleague who is also Indian and single and my wife and family is aware about it. I was very open and honest to them. My questions: 1. I want to file a divorce with my wife, reason is not my relation with another woman, reason is me not getting along with my wife. But she will portray to the world that this is the reason. 2. I've two daughters and I will continue my responsibilities towards them. I'm looking for an amicable divorce but I don't think so my wife wants that. 3. Can she do any kind of case on me for extra marital? 4. Will my GF be involved? I don't wish to involve her as she has nothing to do with my decision as our marriage was already suffering for long? 5. How long does the divorce process take? Will I've to travel to Mumbai time and again? Kindly Guide