There's capital-N Narcissistic Personality Disorder, and narcissism, a trait described as being self-serving and/or selfish.
I have an ex with NPD. It's nightmarish, especially when you get on his bad side. If anyone is interested I can certainly share more of my experiences what it was like to date, go through a custody battle with, and co-parent with him.
People who are narcissistic are just self-absorbed and/or selfish. I think of my mother, for example, who I also consider co-dependent, who asks questions and doesn't wait for answers, who tries to control me with unsolicited advice and mico-managing my life as an adult, whose recollections of my childhood are self-serving, and who can't handle conflict or anger without making it about her and her feelings, and/or a referendum on who she is. It's exhausting. Or my sister-in-law, who is vain and self-absorbed and manipulative, or my AH, who is so wrapped up in his own id and ego that he can't see how his actions affect other people except on the most surface level.
As a co-dependent, I used to take all criticism personally, even if it wasn't directed at me. I took offense *for* people and bent over backwards to make sure everyone felt included and was happy, even if it meant being in bad or uncomfortable situations myself. In my FOO, my feelings didn't matter. I coped by making the parents happy, and took these coping methods with me into adulthood.
Codependency could certainly describe a type of narcissistic behavior where one devotes his life to another and fawns over someone in order to get self-worth-while at the same time feeling resentful, bitter, and contemptuous.
I can see this. It's what we talk about, trying to fit someone into the role, instead of finding someone who fits the role. We try and shove our As into the "responsible spouse and parent" role and get crazy with anger and resentment that we can't fit a square peg into a round hole. Ultimately, we learn this resentment is within our control, right? We are capable of changing our lives.
Unfortunately for folks with NPD, there really is no changing their lives. This is a life sentence. They're considered untreatable.