Lyric discussion by sappyman101 

My interpretation of the song is as follows: Only when she marries someone else and understands happiness as it "should" be, does she finally break down and cry. I feel like the crying is symbolic of an outpouring of emotion, whether it's negative or positive (in this case both for he and his former lover respectively), and that emotion never fully blossomed when she was with him, therefore she never cried in front of him.

Only now does he realize the importance of the tears, or lack there of, and it kills him that he didn't understand earlier. And while he claims (in the first verse) that he's relieved, really he's regretful and wished that such and outpouring of emotion (crying) happened when they were together, because then he might have realized ("How was I supposed to see?") without her saying.

All in all: Damn, I'm a fool, but how was I supposed to know if she never did that stuff with me. (But moreso in disbelief and regret than actually "NOT" mentally comprehending.

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