I've also been diagnosed as having TRAITS of both borderline and narcissistic. I also like introspection. I find it amusing and if it never amounts to anything more than that, if i never come to any conclusions, well then, it has been an enjoyable hobby, a pleasant way to pass the time.
I always remember how wounded i was when my ex-husband said, "You think and think and think, but what you come up with is not that original."
The pain of that has passed tho and i just accept this is a dynamic i LIKE to indulge in. I'm under no illusions that it's purposeful or will lead to any ground-breaking thesis. It's just how i am.
Also, the problem for me is that personality disorders are said to occur regardless of mood state. For example, self-defeating personality disorder traits do not occur just when depressed.
When i'm hypomanic and euphoric it might look like narcissism but i also love all of humanity too and that's not narcissism at all.
When i'm depressed i am intensely bothered by traits of self-defeating personality disorder. It's very painful.
When i am mixed, i am extremely borderline.
DSM says diagnoses of traits of personality disorders are only valid when they cannot be better accounted for by mood disorders. So i can't see how i can have both.
I like the approach of solving problems in therapy regardless of diagnostic label. The diagnoses are largely for the purposes of billing insurance companies, anyways.