Here is some thing to really consider. Narcissistic Personality Disorder is very similar to Borderline Personality Disorder. And to further complicate things you could have both with one being a little more dominating. Or you could only have one with many of the other's traits without fully meeting the criteria for both. It is very common for people with either to either share some of the traits of the other or even qualify for both. It's estimated 25% of BPD also have NPD.

I have a lot of the BPD but not the self harm or suicidal, also not the needy or clingy. But enough to meet the criteria for BPD. I also have enough to meet the criteria for NPD. In fact the way I am some doctors would say I'm just NPD and some would just say BPD and some would say both. It can be that difficult to diagnose.

One of the main differences is a Narc will not go for help unless there is no other option left or they are forced to. While a BPD is much quicker to seek help. Both have rage and mood swings and underlying insecurity issues. I share traits for both, more wit npd but the ones with bpd are undeniable. The splitting, disassociation, and fear of abandonment, except i pretty much expect it and am use to it. I also have Grandiose feelings some times enough to make myself sick lol.

So it's not always so black and white after all