Is it permissible to inform a friend who wears tight clothing that the reason suitors reject her is her attire and behavior? Is it permissible to orchestrate a confrontation with her on the street and tell her, "You are doing this to yourself"? And what should be done to make her receptive to advice?

It is not permissible to recommend an immodestly dressed girl for marriage, because the advisor is entrusted, and people's rejection of her is correct. The first approach, by clarifying people's rejection of her, is good. As for the second approach (a person harassing her), it is not permissible, as it contradicts wisdom and good admonition, exposes the one who does it to harm, and is an evil deed. What is required is to admonish her with wisdom and gentleness through pious girls, and to give her Islamic books and tapes about hijab (definition) and chastity. If admonition does not work, it is permissible to shun her as a deterrent.