There is so much info out there now a days about NPD and lots of good books.
Relationships are another matter and when they are a problem there is only one solution, go within, work on yourself and talk to a supportive or recovery friend so you can get your head on straight.
Otherwise, have you hear of EFT, it really helps get relief for emotional pain in minutes, it's like emotional acupuncture but instead of needles you tap on those spots while you're upset.