Marriages require work, love, and determination to succeed. In emotionally balanced and healthy individuals, these ingredients may be available, and the marriage a mutually satisfying one. Unfortunately, for some, it seem that no matter how much effort is put in, the other party is not reciprocating and in fact continues to behave in ways that are bewildering, hurtful, and at times incomprehensible. One possible explanation for this is a personality disorder. There is a segment of the general populace that is afflicted with one of these personality disorders, one of which is narcissism.

Narcissism is an extremely relationship-destructive disorder. It is more common in men, and may lead to behaviors that are selfish, hurtful, and upsetting to the non-disordered partner. While only a mental health professional can make the diagnosis of narcissism, it is very helpful to understand the signs of the disorder. Here are 8 signs of narcissism:

1. Lack of empathy toward others. Your spouse might not be capable of "walking a mile in another person's shoes." This can cause your partner to act in ways that are callous and self serving.

2. A sense of entitlement in life. You spouse may walk around expecting preferred treatment.

3. A willingness to exploit others to get what he or she wants.

4. An inflated, or grandiose sense of self worth. More than a healthy ego or sense of worth, this is an extreme version in which accomplishments are exaggerated.

5. A craving or need for a supply of admiration and praise from others. This "narcissistic supply" is like a drug, and the narcissist will generally pursue all avenues available to obtain it.

6. Idealized forms of thinking. In other words, your partner may fantasize about ideals in love, beauty, or power. You may be idealized for a time until you stop offering enough narcissistic supply or are otherwise found to be imperfect - then you may be completely devalued as nothing, with very little grey area.

7. A haughty or superior attitude. This may be evident in dealings with or conversations about others.

8. A high degree of jealousy toward others over their accomplishments. Anyone who takes attention away from the narcissist is an enemy. Your spouse may even get enraged at the accomplishments and recognition of others.