María de Zayas' play, La traición en la amistad is, like her novellas, a tale of amorous intrigue and conflict between sexes. The plot is based on several triangles made up of three galanes (Gerardo, Juan, and Liseo), four damas (Fenisa, Marcia, Belisa, and Laura), and a pair of servants (Lucía and León). For the most part their relationships are guided by the traditional treatment of love in the comedia. At the outset only Marcia and Liseo love each other, but their love is complicated by other characters. Gerardo also loves Marcia, and he spends a great deal of the play trying to be with her and complaining when she rejects him. While she does not dislike Gerardo, she perceives his love as a threat to her independence. Fenisa, Marcia's friend, also loves Liseo and, despite her friendship, she tries to disrupt Liseo's courtship of Marcia. In addition, Liseo is haunted by his prior dishonorable treatment of Laura, whom he seduced then abandoned. Her appearance and resulting friendship with Marcia is an even greater barrier to Liseo's love.
Stroud, M.D. (1985). Love, friendship, and deceit in la traicón en la amistad by Maria de Zayas. Neophilologus, 69(4), 539-47. doi:10.1007/BF00399529