Dry Ice song meaning

This is one of the songs that Armstrong wrote about his best friend's sister.
The narrator is expressing his genuine feelings towards a girl that inspired him to write this song. He is deeply in love with her, keeps dreaming of her and wants her to be by his side, but he doesn't know if she feels the same way. He doesn't find enough courage in himself to write her a letter, his pen is "writing wrong" and he decides to express his feelings in a song, hoping that she will hear him and understand how much he really needs her.