Am I wrong for not telling her?

So I have this friend. She messes with two guys who are no good. I have told her soo many times to leave them alone. Even when they do the worst things to her she never leaves them alone. One of the guys talked to her cousins family. And the other is trying to talk to the girl we hang around everyday. She entertains it. I didn’t tell her about it while we were t school because I know she is going to try to fight her. So I said nothing. But it’s old at this point and the guy she is still messing with even after I told her what was going on. She told me I was jealous and didn’t understand cause I’m a virgin but it’s been a couple months should I tell her? He is also trying to talk to another girl she hangs with. I don't know what to do. I don’t want to be in the middle of it
Am I wrong for not telling her?
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