My Sister after Marriage issues because of Husbands sisters and their husbands

Dear Sir / Madam, My sister married recently to the person she loved, both loved each other but my sister husbands family were not accepting for this they always call to him and abuse my sister and they are forcing my sister divorce him, sisters husband is not taking care of this issue with their parents, frequently they call him and harass my sister they abuse her a lot, they both loved each other but since their parents are brain washing him to leave her every day he is quarreling with my sister, 2nd Feb was my sisters birthday, then after 3rd morning at 5am he left home and didn't returned yet, and he says not to call if she is calling him, he once himself called and said I'm with my family don't call now , on call my sister heard her husbands family saying something and abused her, she attempted suicide by hanging herself to ceiling, but unfortunately she was saved, my entire family is disturbed, my mother had sudden pain in her chest seeing all these, i'm requesting your guidance to how to resolve this issue, he is unable to convince their parents and always listening to what his sister is saying and harassing my sister please help my sister, before she takes extreme step, we dont want her to lose her life