Lota, as she was known, had a relationship with the American poet Elizabeth Bishop from 1951 to 1967. Their relationship is depicted in the Brazilian film Reaching for the Moon, based on the book Flores Raras e Banalíssimas (in English, Rare and Commonplace Flowers), by Carmem Lucia de Oliveira, as well as in the book The More I Owe You, by American author Michael Sledge.
In 1967, Soares joined Bishop in New York, after a period of extensive hospitalization for a nervous breakdown. The same day she arrived in New York, 19 September 1967, Soares took an overdose of tranquilizers. She died several days later.
Elizabeth Bishop, One Art: Letters. Ed. Robert Giroux (New York: Farrar, Straus, Giroux, 1994).
Carmen L. Oliveira, Rare and Commonplace Flowers: The Story of Elizabeth Bishop and Lota de Macedo Soares, translated by Neil K. Besner, (Rutgers University Press, 2002); reviewed by Emily Nussbaum 
Schuma Schumacher and Érico Vital Brasil, eds. Dicionário Mulheres do Brasil (Rio de Janeiro: Jorge Zahar Editora, 2000), pp. 335-336.
Michael Sledge, "The More I Owe You." (Berkeley: Counterpoint Press, 2010).