Who is Jessica Culver from Deal Breaker and what is their importance?

Jessica Culver is a successful novelist and the oldest child of Carol and Adam Culver. Jessica is Kathy and Edward's older sister. Jessica Culver has returned to New York to teach at NYU for a term and she accidentally re-connects with her ex-lover Myron Bolitar four years after their breakup. Jessica admits to being self-destructive and to making less than wise choices. Jessica realizes that leaving Myron for another man was a mistake. Jessica is stunningly beautiful but refuses to let others objectify her based on her looks.