We don't have any such law, where foreigners are permitted to file divorce in India. If she and her husband both are hind and married under Hindu Law, they may file a divorce on the grounds of mutual consent in India. I am not sure about this as Indian law never permits for divorce if the marriage is not solemnised as per Indian law or India.
For that both have to appear for mutual consent before the court. Or else contested petition for divorce can be filed in India on the grounds of cruelty by the wife.
If she is unable to file divorce from India, then only remedy is to file divorce in Nepal as per Nepal laws.