One woman aged 60+ married is being mentally tortured by her husband what should she do?

the womans husband is being tortured mentally and not physically from theday she got married, her husband was into buiness but could not do buisness properly and so no earning, but still she got monetary help from her fathers house so she could run the daily expenses and the expeneses for her 2 children's school fees. gradually as years ped by the husband did not respect the woman and insulted her in each and every way, and she used bear those insult. and now when their children have grown up and married he still hasnt changed his nature and behaviour. now the children are doing their buisness are earning but the husband still goes on insulting his wife he screams at her like anything without her fault. Now the children have grown up and they cant see all these things happening to their mother instead they make thier father understand but then he starts sreaming at them and their respective wives. so it is my request to please help them and guide them so as to what they should do. there is no peace in their house.