One Desire by Rachel E Rice

When Tyler Burns graduates from a prep school in New Jersey and is the valedictorian of her prestigious high school, she assumes that her working class background will take her only so far. And it probably would have gotten her a working class stiff like her father. But she gets more than she expects when she meets Brandon Charles a Princeton graduate, hot as the noon day sun with blue-green eyes, sexy good looks, and a body to bring her to her knees. It's no wonder he's engaged, and he's expected to marry within a week.

Tyler accepts a ride home from the frat party from Brandon, never intending to end up in his bed, but she does. And if things can't get worse, it does. She stays with him a week and in that week most of it is in bed. He promises her he will call off his wedding. And she believes him. She waits for him but he never returns that night, or the next, or the next.
Five years pass and Tyler graduates from college, and on that day Brandon Charles strolls back into her life in a restaurant with a beautiful girl, and Tyler is his waitress.