Addiction is a coping mechanism. Addiction to drugs, alcohol, prescription pills, business, work, shopping, food, gambling, sex and so on. You can become addicted to almost anything. As Gabor Maté states, in order to treat addiction we have to first understand its purpose.
“It is impossible to understand addiction without asking what relief the addict finds, or hopes to find, in the drug or the addictive behaviour.” - Gabor Maté, In the Realm of Hungry Ghosts