There are definitely a lot of people who like to throw around DX labels. I really try to avoid it and just focus on a person's behavior and how it affects me, but, for example, with my dad, my therapist really thinks he has NPD, and understanding NPD has helped me heal. Understanding a bit why he acts the way he does, has helped me moved on in some ways. Likewise, there are a few people in the course of my life I have suspected have some BPD, I don't really share this publicly or say it to them, but what I do actually is focus on their behavior and try to understand what's behind "bad" behavior that affects me and just deal with the behavior.

The only person who can DX and should DX is the person's provider. Even people who I think have this or that, who knows? Because I'm only seeing one side of the person and in certain situations. Their provider will have the whole picture.

It's so much easier to just go by the person's actions, right? If the person is a jerk to you then you just say, the person was a jerk, not diagnose every person who might have been terse with you as NPD, lol. (I mean general "you" not YOU, lol.)

I think people using psych DXs as put downs or insults is a really crappy trend.