razzia manzur asked 4 years ago

I have a sister who is a born Moslem and got married to a non Moslem. they have been away for almost 20 years and we have no clue as how they manage their daily lives especially when it comes to their religion. My sister  performs her 5 x daily prayers, fast during the month or Ramadan, I have no idea to zakat if she is able to do so. she has two daughters who are non moslems as well due to his husbands request.
Few days back, I get a call from the husband of my sis, after a fight that has been happening for two months now. he is not working, with history of drug abuse and daily takes alcohol. he is not mentally stable as he accuses my sister of having an affair with another man. my sister works on line and has no chance of leaving the house. I learned from some of their friends and relatives of the man that my sister has been emotionally and mentally abused by the husband. I have tried to ask my sister to leave the husband and repent to Allah but she believes that Allah will answer her duas even without her leaving. But what happened the other day reached a point that a sheriff came to visit them and because of my bro in law manipulative behavior the police left believing all his lies. I feel helpless and need your guidance