The following are some of the characteristics of narcissistic personalities and how they affect relationships:

Shamelessness - A person who is narcissistic in an unhealthy level is going to not process shame, at least not the same way others will. This means that things that would make a normal person feel ashamed, will not affect them the same way. So, manipulation, toying with emotions, using, and abusing people is not going to affect them. They won't feel shame over it, which makes them dangerous. To them, using someone for sex is not shameful because they only see their side. They wanted it, so they got it, regardless of how it affects the other person or people involved.

Distorted self image- A normal person can recognize flaws in themselves. While it may not be easy for them to admit that they could be more patient, humble, etc. they know it is the case. With unhealthy narcissism the person may see himself or herself as perfect. Thus they have no motivation to improve, and will NEVER change.

Tear others down- Usually a narcissist must feel superior, so if their worth is at all threatened, they will build themselves up by diminishing others. They will put someone else down, debase them, degrade them, or even defile them in order to feel superior. This is especially common in a relationship. If you are married to a narcissist, they may feed their ego by constantly tearing you down, which means you could live for years believing you are of little worth, and your only purpose is to serve them.

Entitlement - Narcissists consider themselves to be special, and superior, which means they often expect to be favored, and that their wishes will be complied to automatically, and without question. They feel entitled to such treatment, so when it does not occur, they often have unreasonable anger or narcissistic rage.

Disregard for others- For most people who suffer narcissistic disorders, other people are there only as a means to meet their needs, and thus, their only thought to others is how they can supply them with something they need. A person who does not comply to their will, who does not agree with them, or who does not think of them as superior as well might as well not exist in their view. Because of this, they often treat people poorly, or inappropriately, as in their eyes others are merely a tool to be used by them.