I believe addictions are about relationships. This idea is explored in many blog posts on this site, including: a discussion about Tiger Woods, the Kaiser ACE study, the loss of social connection, and autism. In addition, the following video clips provide you even more insight into why I believe addictions are ultimately about relationships. Although each clip can stand on its own, if you watch them all you will understand much better the complex puzzle of addiction.
I also suggest reading the top five things you should know about addiction.