Was I wrong to end my friendship?

She probably views you at that "gay friend who she can complain to". Every girl needs one of those right? Sarcasm. Anyways, she needs to realize she's being selfish. You weren't being too harsh, you were simply telling her the truth. You have been way too nice to her anyways. If I were you, I would've stopped talking to her ages ago. Since she does think she's a narcissist, she's using you to vent. It's not fair for you, because she never listens to you. I don't see a point in this friendship.