I'm currently listening to an Elvis compilation album, and I noticed a couple things about "I Want You, I Need You, I Love You." Some of the "heart"s in the recurring line "I want you, I need you, I, I love you / With all my heart" have either a melisma or a sort of stutter, which - to some degree - represents that "all." The wanting, needing, and loving isn't limited to just one note or one pitch.
More significantly though, I noticed a large interval between the two syllables of "apart" in the line "'Cause I die every time we're apart." I'm pretty sure the interval there is an octave (between C notes), which helps to demonstrate that distance.
