It seems to me that this song is about alcoholism, specifically his denial about the increasing hold it has on his life. Alcohol is a way for the character in the song to escape from the confusion and ugliness of the world to a place where everything is "quiet" and where anything that is said holds a "truth" to it. To minimize how much he relies on alcohol, he calls it "just a habit" and attributes his slurring to only being "confused." But the entire time, the problem is escalating until it's poised to take over his whole life.
It seems to me that this song is about alcoholism, specifically his denial about the increasing hold it has on his life. Alcohol is a way for the character in the song to escape from the confusion and ugliness of the world to a place where everything is "quiet" and where anything that is said holds a "truth" to it. To minimize how much he relies on alcohol, he calls it "just a habit" and attributes his slurring to only being "confused." But the entire time, the problem is escalating until it's poised to take over his whole life.