People fall in love with narcissists for so many reasons. Some of them have to do with the person who suffers from narcissistic personality disorder (NPD), whereas other reasons have more to do with the intoxicating nature of feeling like “the chosen one." Of course, each person with NPD is an individual, with their own personality, appealing characteristics, issues, etc. However, what they do have in common is a lack of object constancy (the inability to maintain a positive emotional tie to someone when they are upset with them), very little emotional empathy for others, and extreme difficulty self-regulating their moods, self-esteem, reactive behaviors based on their emotionally distorted experience of the world.
Why do people fall in love with narcissists?
Some narcissists have other wonderful qualities.
Many narcissists have other wonderful qualities, which may include: power, intelligence, good looks, a good sense of humor, charm, liveliness, fun, prestige, and other commonly appealing qualities. Of course, there are plenty of narcissists who do not have any of these qualities, but people are often surprised how easy it is to fall in love with a narcissist regardless.
Unconsciously repeating trauma.
Often when people were raised by narcissists, they repeat the familiar pattern of picking someone who unconsciously repeats this pattern from their childhood. Frequently this includes the person trying to gain the narcissist's approval, love, attention, and caring, despite the painful emotional rollercoaster of the relationship. One can think of this as the person unknowingly repeating this familiar cycle because they are unconsciously trying to finally get the positive feelings that they did not get enough of as a child. Of course, they usually do get the outcome they are craving, and more frequently they end up feeling re-wounded.
They can be intoxicating.
Not every narcissist is charming, but the ones that are can be truly intoxicating. At their best, when a narcissist “picks you” many people feel special, wanted, chosen, and find this to be very intoxicating. This is the stage when they are viewing you as the perfect being that they are pursuing, and the average person is unlikely to have any idea how quickly these feelings can change, and what the relationship is likely to feel like when the narcissist does not find them to be so shiny anymore. By this point, many people are so in love and tangled in the relationship, that it can be very painful and difficult to break-up.
Not every narcissist is created equal.
There is a huge range of emotional functioning among people who suffer from NPD. For example, there are narcissists who become icy when they are angry but have learned to filter the meaner things they may be tempted to say in a moment of anger. On the other hand, there are also extremely toxic narcissists who can be cruel, sadistic, and awful the second their mood shifts. A higher functioning narcissist is capable of having a healthier relationship than the lower functioning, more sadistic narcissists.
For the same reason, they could fall in love with anyone else.
People can fall in love with narcissists just the same way they fall in love with anyone else. They meet, they are attracted to them, the person has qualities that they like, and they feel connected to the person. Of course, this does not mean that the person with NPD will handle the relationship’s ups and downs like anyone else, but usually people do not realize this at the beginning. Even when people are exposed to the red flags that they may be involved with someone with NPD, most people ignore these signs, and focus on the aspects of the relationship that they like, feeling hopeful that it will still be good, it will get better, or they can somehow love the person enough/ change them/ or “be worth” the person changing. While these are common desires, many people come to realize that they can not change the person, manage their mood swings, and/or find it incredibly hurtful when the person with NPD no longer treats them like the shiny object that they were at the beginning of the relationship.
The point is…
People fall in love with narcissists for about a million reasons. Many narcissists have other appealing characteristics like intelligence, good looks, humor, power, career success, and outward confidence. While others may not have any of these positive traits. Some people may “fall in love” with someone with NPD due to unconsciously repeating maladaptive patterns from an earlier stage in their life, while others may simply fall in love and weren’t paying attention to the red flags at the beginning of the relationship due to all of the intoxicating feelings of falling in love and wanting this person’s affection.
Also published as an answer on Quora.com.