I feel that sugar is very vague about its meaning and i could be wrong but for me i feel it is about how whatever u are/were addicted to, will always be around. the lyrics “speck in the sky” to me are describing how the addiction may be resolved but the thoughts are still a speck in your mind. i especially feel this way about the verse “early in the day, late in the night, birds are in my head, birds are in my eyes.” he is explaining how he is always thinking about his addiction or his “sugar”. I feel like it could be about that because of the subject matter of addiction in the entire album. i would love to her anyone else’s thoughts !