Who is Delaney Lightfield from Match Me If You Can and what is their importance?

Delaney seemed like a perfect choice for Heath. Delaney came from the society life in Chicago. She doesn't put a foot wrong. She will be the perfect hostess for the people Heath wants to know around town. She enjoys sports but the less brutal type. She likes tennis. She likes opera. Heath and Delaney seem good together except Heath never relaxes around her.