“It isn’t a suitable job for a woman.” 

This is the first—but not last—mention of how Cordelia’s gender makes her ill-suited for her role. This is a repeated theme throughout the novel. Here the lines are especially ironic, as they are said by a female bartender, another role that could be considered unsuitable for a woman.

“She had quickly learned that to show unhappiness was to risk the loss of love. Compared with this early discipline of concealment, all subsequent deceits had been easy.” 

These lines establish Cordelia’s suitability for being a private investigator: She was brought up in foster homes where she learned to lie, cementing her status as an outsider and an unreliable narrator.

“Bernie had needed to be a detective as other men needed to paint, write, drink or fornicate.” 

Cordelia is reflecting on Bernie’s dismissal from the police. The reason for that is never given, but she assumes it must be unfair because the job was his calling. This is the nearest James gets to salty, base language, used here to show the seriousness of the statement. As the reader realizes Cordelia has the same calling, this line helps us understand why she isn’t jealous of Sophie’s life, or Isabelle’s, and how she engages with her work, no matter unsuitable it may seem: She doesn’t feel she has a choice.