You're quite welcome (for the posting of the poem).
Gosh, I guess... I guess the best works of art endure because they leave themselves open to interpretation... and no one interpretation can be said to be "definitive". Why *is* the Mona Lisa smiling? Even Shakespeare - whom numerous scholars insist was explicit about his meanings and requires no interpretation - has an equal number of scholars only too ready to interpret his work...
For my part, I heard in those two famous lines the distinction drawn between a 'snapshot in time' and the entire parade of an individual's existence. "I did not love 'the you that was' at *this* moment or *this* moment or *that* moment, but the whole panorama from birth to death... the 'sorrows of your changing face'..."
"Murmur, a little sadly, how love fled..." he says. For whatever reason, she did not choose to stay with him, but it gives him comfort to think that perhaps, when she approaches the end of her journey, she'll have the perspective to look back and realize the uniqueness of his love...
