an strange love case

sir, if some male is married and has fallen in love with another unmarried girl. the girl also reciprocate the same deep love feeling. For a considerable period of many months the affair was a secret. But the wife of the man came to know though the WhatsApp chat. she raised widespread alarm and this led to the social bad name to both of them. The girl was doing a job. after this incident the family members of the girl detained her in the house and against her will totally restricted her freedom. Even the mobile was snached. Job was resigned.they are forcing her to marry now. Age of the girl is 27 years.the man has tried to divorce his wife but she is not agreed to divorce him at any cost as she know the reason and don't want to contribute to their happiness. Now in above reference my question is is the act of the family members of the girl is justified legally, if not what is the legal remedy. Can the man demand her custody from Court and police protection. if yes what is the competent court and how the same can be done. Man is not living with his wife now and stays away from her generally. Kindly guide.