Harrassment and divorce issue

Hello sir , my sister who got married ro my brother in May 24th this year. Went to her mothers place on the 19th day of her marraige saying that my brother is harrasing and abusing her . Though he is not beating her but he is abusing her and threatening her that he would kill himself. Her parents came with girl first time on 5th day of marraige n started blaming my brother that he is abusing her verbally and hitting his gands on the walls. When we asked he said we had fight which was petty thing . She aleays to stay at her mothers placr. If she doesnt go in the mornjng she wants go in the evenng . We just asked her to stay with husbamd since its a love marraige . On the 19th day she pushed my mother who is a vidow and a patient and banged the door and went to her mother place . Since then the girl nevet came back . Her parents says they want to settle the issue so we went 3 -4times to fix the ossue but everytime the girl says my brother has forced her to drink wven though she likes to dribk alot . Now she started threatening us that she will put harrasment case against me and my family . She is saying im telling wverybody and they are harassing her . Which is not true . They r the ones who r telling people about the whoke issue .pl advice my brother did love and arrange marraige . They both used to roam alot before marraige . Prior to my beother she had a boy frms and she broke with him not sure about the year . He passed away this year