define...

addict:
-to cause to become physiologically or psychologically dependent
     synonyms: adherent, devotee; fanatic; junkie

alone:
-separate, apart, or isolated from others

      adverb: solitary; solely

worthless:
-without worth of no use, importance, or value; good-for-nothing
       without practical value or usefulness

I think of these words when I am reading Tweak. Addiction is only caused and can only be cured your you, and your actions. No one can force you to recover, because relapsing is just around the corner. You do certain things, good nor bad, because you made the decision to, not your friends or your parents. These 3 words resemble the struggle and the reasons of substance abuse and addiction.