Re: Odds he is a narcissist
While I think it's wonderful that you have such loyalty to her, at the same time you have to look out for yourself.
Have you tried to tell her how you feel about her behavior toward you? When she attacked you when you told her about your concerns regarding her dating this guy, did you tell her that you brought them up out of concern for her?
If you want to stay friends and stay loyal to her, you really need to have a serious conversation with her. Point out that you care about her and want the best for her, thus you didn't appreciate being attacked. Let her know that your patience and loyalty can only be stretched so far. Again reiterate your concerns about this guy. Let her know that you think she should get some counseling. If she agrees, offer to go to the appointment with her as a show of support. Also, wait for her while she's in the appointment. Finally, tell her it's her life but as her friend you are trying to spare her from heartache.
If she attacks you after all that, then I suggest that you end the friendship with her. Or at very least, tell her that when she comes to her senses, she can call you.
You must realize, sad to say, that some people just don't appreciate a good friend when they find one. That appears to be the case with her.
All the best to you!