Drug addicts, like all those who suffer, are the terrible gift.
An addict gives you the gift of recognizing your own addictions. Of seeing yourself in the life of an opiate addict. To understand that we are all addicts of dogmatic thoughts and actions that ultimately hurt ourselves and those around us. To recognize actions and thoughts that seem helpful and beneficial, yet are actually hurtful and limiting. (I'm taking about judgement and negativity and gossip and disrespect and critiquing and anxiety and over working and unbalanced living and anything that pulls you away from the people and things you once loved or maybe never gave yourself the chance to love.)
And then, of course, you are also given a gift of understanding the other. Of practicing compassion and deep understanding of those who are not you.