Candy Stripers by Lee Wyndham (1958)

Bonnie Schuyler let herself be talked into joining the Candy Stripers.  As a junior aide at the Medical Center, she lightened the heavy work load each regular nurse had.  But she sometimes wondered why she was there--she didn't plan to be a nurse; it was hard work; she didn't especially like helping other people.  One day she met David, a technician who was interested in a hospital career.  Somehow he made her feel rather special and very grown-up.  (from the back cover)