The Yes Girl — Kathryn Makris

Gwen's favorite word is yes. She says yes to Susan who asks for free math tutoring, yes to any friend who needs help…even a yes to nice but boring Mitch who asks her for dates. Gwen doesn't have a minute to herself. Unfortunately, she hardly has any time for Phil, either. Phil is funny,
handsome, and definitely not boring. And Gwen likes him a lot. When he asks her out Gwen says yes…with delight. But she is still saying yes to Mitch, too. Phil soon becomes tired of being Gwen's second choice, and tells her so angrily. Now Gwen is torn. If she starts saying no, she may lose her friends. If she can't stop saying yes, she'll lose Phil.