Jealousy is often seen as a negative emotion even though it is normal in certain situations -- and may even be a positive thing. However, it can become unhealthy if it turns into an obsession, takes over your life and causes irrational behavior. The difference between healthy and unhealthy jealousy comes down to the way that you deal with it.

Jealousy is normal and even necessary in relationships, according to clinical psychologist Anne Stirling Hastings, author of "America's Sexual Crisis: Discovering Healthy Sex by Healing Culturally Caused Shame, Addiction, and Sexual Distortion.” If you are in a monogamous relationship, jealousy serves as a way to let your partner know that you care about preserving your relationship. Some people like to know that their partner gets a little jealous if they feel the relationship is threatened. This confirms that your partner values your commitment and would be upset to lose you. Jealousy as an expression of love is healthy if both of you are being honest -- and not accusing -- about your feelings, according to Hastings.

Jealousy can let you and your partner know what you both want and do not want in the relationship. Every relationship has its own limits, and it is up to you and your partner to define your own, according to "The Marriage and Family Experience: Intimate Relationships in a Changing Society," by Bryan Strong, Christine DeVault and Theodore Cohen. Some couples may be OK with casually flirting outside of the relationship, while other couples may discover through their jealousy that they are not happy with either partner getting too close to another person. Using your jealousy as a tool to draw the lines in your relationship will work only if you and your partner have honest talks about your feelings and come to an agreement on the terms of your relationship.

Jealousy can be an important emotion to pay attention to, but it can also pre-occupy you to the point of obsession. When it becomes an obsession, it can cause you to become possessive and paranoid. For example, a jealous boyfriend may constantly check his girlfriend’s phone, ask her not to be friends with any other males, or try to prevent her from leaving the house without him so that he can be sure she won’t flirt with other men. Jealousy can lead to violence.

In "Understanding Emotional Problems: The REBT Perspective," cognitive behavior therapist Windy Dryden explains that some people may have no real reason to be jealous, but they may make up evidence to support the fear that their relationship is in danger. For example, a woman might be jealous whenher husband talks to another female whom she fears her husband thinks is attractive.The jealousy may become so irrational that she starts to become easily threatened and begins to believe that her husband is attracted to every woman he meets.