Take some time to browse around. Addiction, or dependence, is a subject usually associated with drugs, cigarettes or alcohol, but, in reality, one can become addicted to virtually anything.
Many therapists see promiscuous sexual behaviour as an addiction.
Gambling can become an addiction. Overeating can become an addiction. This type of addiction is just as severe as physiological dependence. The behaviour or abuse exists despite significant impairment in social and occupational functioning, as well as negative effects on health and finances. The individual often denies that there is a problem, or tends to minimize it, despite evidence to the contrary.