It's about a thought, which turns in to an emotion which turns in to an action. The thought is: "This life s**ks, the emotion is: I'm so sad I need to forget, the action is: "dull the pain by the use of whatever will dull it.
If we can change the thought (which may not even be reality) we can change the emotion and action that follows. It's a very sad situation that unfortunately so many relate to and buy in to.