Addictions could be behavioural (for example Gambling) or substance related (for example drugs or alcohol). Irrespective of their basis, addiction affects the person they possess and the people around them. For instance, the families, co-workers and associates of the person suffering from addiction are affected adversely by it. Wendy Redden in her article lists nine ways to deal with persons suffering from addiction:
http://www.lifehack.org/278345/9-things-remember-when-dealing-with-addicted-loved-one