Child custody without divorce

My wife and i are seperated from last two years. we got married 3 years back. We got a son after one year of marriage. When my son was one year old my wife ask me to go her parental home. I respected her wish and took her there. Since then she has not returned back. She demanded me to to come every month there and wear her all expences. I did it for one year. Suddenly i fealt cheated when she denied to come with me. Last year april 2015, i went her parental home to take my son and wife back she, her siblings and her parents abused me. And warned me if i go back their home they will put charge on me for violence and rape of her female family members. Niether I nor she has taken any legal action. I do not want divorce coz i have no desire to marry again. All i want is my son's good health and his custody. I have not seen him from last one year. Now he age 2 years. Is it possible that i keep seeing my son every month untill i get his custody. Is it possible to get custody of child without divorse. She want me to file divorce case, that her father called me and told me. I and my wife do not have any kind of communication from last one year. She never recieve my call.