I have autism/Aspergers, so I carry with me the "apparent lack of empathy"

The book "How to win friends and influence people", by Dale Carnegie, was a God send to me, it it might help you learn how to cope with your NPD.  To sum up the key points:

 - Become genuinely interested in other people. 
 - Smile. 
 - Remember that a person's name is to that person the sweetest and most important sound in any language. 
 - Be a good listener. ... 
 - Talk in terms of the other person's interests.
 - Make the other person feel important – and do it sincerely.

Make these a rules a part of your habits and you will have a far easier time in work.

Buy the book, read it cover to cover

And, get professional help, as needed.