I just completed a class that discussed some of these issues.

Borderline personality disorder:
Cluster B: Dramatic, Emotional or Erratic
A pervasive pattern of instability of interpersonal relationships, self-image, affects and control over impulses

Narcissistic personality disorder:
Cluster B: Dramatic, Emotional or Erratic
A pervasive pattern of grandiosity (in fantasy or behavior) need for admiration and lack of empathy


The alcohol, guns, weird behavior while she was at your home would be huge red flags for me.

I would be cordial and consider letting her know that if she has a serious emergency, she can call you.

Just saw your other post:
I agree, don't even think about having a conversation with her when she has been drinking.
And I would also keep your conversations relatively short and relatively infrequent.
Perhaps this way, there will be less room for arguments and she will appreciate your friendship.