I have experienced what you've described only it's usually been when I'v broken up with a boyfriend. I begin obsessing in my mind of what I could do or say. Fortunately, it has gone away and I'm now in my late 60s so romantic relationships aren't something I think about these days.

Examining both your and my own behavior it seems like a reaction to rejection and the hurt that causes. With a relationship, you can walk away and then get over it. (Interestingly, one of my ex's whom I felt the worst and longest about has once again become a friend after 43 years. How about that? But I'm no longer in love with him which sure helps!) In your case, it's far harder with a father whom you feel belittles, excoriates, or just plain doesn't care about you the way you want him to.

But even if that is the problem, the question is what to do about it. I agree with the others that therapy sounds like a good solution to help you make sense of the situation and develop some strategies to deal with your father. But try to keep in mind that as someone w/ NPD, he is sick and therefore, unable to give you what you'd like to have or need. It's sad but it's also manageable. You just need to learn ways to do that.