I "loved the sound this makes."
I didn't really get that the last verse was an "anti drug message." It seemed more to me like it's a "who can you trust" message and that the drugs were incidental.
I loved how the guitar was used as a lyrical device to tie together the stages of the protagonist's life. And I loved how the loss of it emphasized the emotional importance of it.
I really loved the subtlety of the guitar music. The rhythm line was good, but the enhancements were soooooo perfect and subtle that they would be easily missed at a casual listen, but they were vital to the performance. Sorry I don't have any suggestions for improving this, but I didn't hear a thing I didn't like.
I remember when songs like this (i.e. songs with meaning and emotion) used to make it onto the radio. That probably labels me as "old." I am guilty of being old.