Who are the characters in the poem "A Valediction: Forbidding Mourning"?

This poem contains two characters, a man and his wife. The man is leaving on a long journey and says "Goodbye" (a Valediction) to his a wife he loves. He tells her not to cry or be sad (Forbidden Mourning).

Isaak Walton, a friend of the author, John Donne, said that Donne wrote the poem for his wife when he left on a diplomatic trip to France. His wife and pregnant and not feeling well. She begged him not to go but Donne felt obligated. Two days after arriving in France, Donne had a vision of his wife with a dead child in her arms. He sent a messenger back to England who returned with the news that Donne's wife had delivered a dead child the day he had the vision.