Who is Marinne Fortescue from The Favored Child and what is their importance?

Marianne is the young woman Julia sees leaving Dr. Phillips' office. Julia will later learn that Marianne has an eating disorder. Marianne and Julia eventually go to see Dr. Phillips together, both declaring that they aren't benefiting from his treatment and ending their sessions. It's Marianne who is handed the task of overseeing Julia and James as they are courting while Julia's mother is ill. She teasingly tells them that if they're going to hold hands while she watches, she might as well not be there.