My friend Alice is going out with Bob. Myself and others have seen Bob acting inappropriately with other women (getting very close and caressing) multiple times and we suspect he has slept with other people.

Recently, Bob was acting inappropriately with another women at a bar when Alice was in another room. I confronted Bob who got very defensive and reacted violently, just as Alice entered.

Later that night another friend (Christine) told me in confidence that Bob raped another friend (Daniella) last year. Daniella does not want to press charges against Bob and doesn’t know that Christine told me about the assault.

Alice continues to be with Bob despite me telling her about Bob's multiple "normal" infidelities. I want to protect Alice by telling her about Bob’s assault. But I can’t tell Alice without breaking Christine’s trust and Daniella’s privacy.

(Names have been changed).