Personally, everybody who I allow in my life fits in one of two spheres of people; friends and minions.

People who are placed in my friend sphere are people who are loyal, accept me for who I am no matter what, and get along with me well. Everybody in my friend sphere know about my narcissistic and sociopathic traits and they know that I frequently lie and manipulate people and hide behind a mask to protect myself, yet they understand that I'm the way I am because of my past. People in my friends sphere are the only people in the world that I have any empathy for and the only people that I would make any personal sacrifices to please. As this time of writing, I have 3 people in this sphere. Family can make it in this sphere but none of my family has ever cared enough about me to even want to get to know me at this point so I've given up on my family.

The minion sphere is for anybody in my life that I keep solely to fill a specific purpose. This purpose is typically either business (money or otherwise), sexual, boosting my ego, or somebody to emotionally drain when I'm depressed or otherwise at my worst. While in rare instances, somebody from my minion sphere makes it to my friend sphere, in most circumstances, they are booted out of my life the moment they outlive their usefulness.

Finally, while I agree that family have a greater chance of connection, ultimately people with PDs be it ASPD, NPD, or BPD are generally the way they are because of abuse from their family or an otherwise unstable household.

The best chance that anybody outside of the norm has of having anybody care about them is carefully screening people who enter their life and only accepting the highest quality people into their inner circle.