There are a couple of different ways you can help your friend. Most of all, be there for her to talk to. You can help her plan a gettaway from this abusive person. That's providing that she is not in danger of having her life taken away. If that is the case, then contacting the authorities in her country is the best thing to do IMO.

I have to tell you though, to be aware that she may become angry with you for doing that. She may not be ready to leave the situation and cannot think clearly about her situation and the danger there. Talking from experience, when one is in the situation of being abused, the abused feels unworthy, feels responsible for the abuse. She may love this person who is abusing her, even if it is a distructive love. Be prepared for the fallout.

You are wonderful to care so much for your friend and want to help her. Go with your gut instinct and how dangerous you feel this situation is. I wish you much strength and luck in dealing with this situation.

I lost a dear cousin to domestic abuse. I wish so much that she had reached out to someone and told them what was going on so we could have helped her get away safely.

Hugssssss
J