Jackman suggested that Aronofsky cast Rachel Weisz as his character's wife. The director, who was in a relationship with the actress, had originally hesitated to show the studio signs of favoritism in casting Weisz. With Jackman's earnest recommendation, the actress was cast as Izzi/Isabel. For her role, Weisz read books and first-person accounts about people who had terminal illnesses. The actress also visited hospitals to see young people who were dying and under hospice care. "There were a few days where I was in the headspace where I could say: 'I could go now'," said Weisz.