. It is possible for the person to have addiction symptoms that are predominately psychological in nature. A good example of this would be gambling or internet addiction. This means that they feel the need to engage in the behavior in order to cope or because they have a deep urge to do so. When it comes to alcohol and drugs the individual will usually develop both a physical and psychological addiction. The way this usually happens is that the person develops a psychological dependence first of all, and this drives them to keep using the drugs until they become physically addiction as well.
When you psychologically dependent on alcohol the person is mentally dependent on the substance, and can alter behavior or mood. When a person is physiological dependence on alcohol, the individual has an increased tolerance towards alcohol.