Husband not living with Wife since 3 year wife want to stay what to do

Sir,My Sister is hindu got married on june 2015.Because of dispute between husband and his father on May 2016 , Husband stopped talking to her. Her husband works in Delhi. And her father-in-law works in Uttar Pardesh and family resides in uttar pradesh only. She lived in Uttar Pradesh with Father in law and the family. But After May 2016, Phones got switched off and husband stopped to talking to her and his family. On the hope that everything will get better, she stayed there till Feb 2017. She came back as the family blamed her presence as a reason to their son's anger. Now its been 2018. We also tried meet her husband and get everything right. But it didnt work out. Now we got to know from sources that husband is planning to remarry. And he is waiting for 3 yrs to complete the marriage. As he will have grounds to divorce her, since they havent consummated their relationship. All my sister wants is to get back to her husband. Do we have any legal resolution in this matter.