Your friend has a distorted view of forgiveness. The research is clear that in situations like hers forgiveness must follow a different course. Women who have been abused by their husbands forgive too quickly and too easily and this can actually make the situation worse. But you are not the person who can help her. She needs a professional to help her learn some better boundaries. I’d encourage her to talk to someone where she worships or a therapist. For therapists she can find one in the “find help” tab at the top of the page.