This poem conveys the idea that we cannot predict where life will lead us. Further, it also illuminates the hopeful idea that love is always possible. The speaker, evidently, lived most of her life "striv[ing] to dance, half blind with tears." It sounds as though the years before she met the person whom she addresses in the poem were unsatisfying and solitary; she describes their path as "narrow and apart." She must have felt restricted, confined even, and wanted to be free (to dance and to sing) but, perhaps, she was afraid or unable to be. It seems as though she felt very disconnected from everyone and everything, and, yet, despite the painfulness apparently associated with her past, the speaker claims that "it led [her]" to her loved one and the love they now share. The speaker no longer "drown[s] in tears" but can, figuratively, sing.
One could say that the overriding theme of the poem is how good can ultimately come from bad. The narrator closes her eyes and thinks back to her younger days, when she was a shy, sensitive wallflower, deeply upset because she was unable to dance. (Or perhaps no one asked her).
Yet those sad years, with all their tears and many disappointments, eventually led the narrator towards her lover. She didn't realize it at the time, but each painful moment passed sitting out the dance brought her just that little bit closer to the man she loves. Her voice no longer choked by tears of loneliness, the narrator is finally able at long last to express the immense joy that resides deep within her soul. The silence of her younger days has itself passed into silence, replaced by words of love. The bad years of old have given way to good.