Let that be your last option, the one that Nixon suggested. I think the reason she lashed out at you like that was, perhaps, there was a bit of truth to your words and although you were giving helpful advice, she may of saw it as you telling her what to do or you saying she was doing something wrong. It's a case of where constructive criticism is taken as simple criticism, which isn't a good thing on her part. My advice though, it's a very volatile situation, so I think you should leave it, you have to be careful when you help someone and when you don't, some people simply won't accept help and don't want help. In that case there's not much you can do, you don't have to drop her as a friend, but it might be better if you leave the issue alone. Even if you see it going down a bad path, if she isn't willing to accept your help, then there's not much you can do.