A pathological, dependent relationship with another human being.
Co-dependency was first identified by researchers who were looking at relational dynamics within alcoholic families. They found that family members in these homes reacted similarly, forming their own compulsive behaviors and obsessive thinking patterns in conjunction to the addict. Today this term is used to describe a constellation of behaviors that arise in members of dysfunctional families that resemble an addiction to another person.
Just as an addict is obsessed with thoughts of his/her own drug or patterns of behaviors, the people who try to maintain relationships with this addict become obsessed as well. Typically, co-dependents are able to tell you everything about the most dysfunctional person in the family, but have little awareness of their own needs and desires. Often the co-dependent causes more chaos in the family than the addict due to unresolved fear and anger, disconnection to self, and irritability. Co-dependents often have little sense of self and constantly look outside themselves for validation, self-worth, and safety. They become caretakers of unhealthy family members to the exclusion of managing their own needs. They believe that somehow they should be able to control the behavior of the addict and see themselves as long suffering or as a martyr. The more the co-dependent over-functions, the more the addict under-functions and the cycle continues.
Usually the combination of therapeutic intervention in conjunction with 12-step involvement is sufficient to change these ingrained behaviors, but co-dependents may need in-patient care if they are unable to interrupt this pattern of behavior with out-patient counseling.