Speak for the Dead by Margaret Yorke USED

Condition: Fair

Summary: Carrie Foster was still young when she started breaking the law. And she took to it like a duck to water. Gordon Matthews had transgressed only once, but his crime was far more serious. A pity Carrie didn't suspect anything when he proposed to her. But then, why should she? Gordon looked presentable now—and prison had given him time to invent a new past.
Nicholas was different—a shy young man, eager to please—and for Carrie their affair began as an amusing diversion. A bit of harmless fun, and Nicholas need never know about her other life with Gordon. But there was something Carrie didn't know either...