The speaker of the poem
The speaker of the poem is the main character who's preparing to go on a far journey and bidding farewell to a lover. He/she alludes to the possibility that they might never see each other again and that the journey to another shore might be his/her last.
The lover
The speaker of the poem is standing in front of his/her lover, and this character is crying over the upcoming journey that might separate them forever. It is left unsaid whether the lover or the speaker of the poem are male or female, which makes the poem a universal allegory of lovers' parting.