The Elizas by Sara Shepard

When debut novelist Eliza Fontaine is found at the bottom of a hotel pool, her family at first assumes that it’s just another failed suicide attempt. But Eliza swears she was pushed, and her rescuer is the only witness.

Desperate to find out who attacked her, Eliza takes it upon herself to investigate. But as the publication date for her novel draws closer, Eliza finds more questions than answers. Like why are her editor, agent, and family mixing up events from her novel with events from her life? Her novel is completely fictional, isn’t it?

The deeper Eliza goes into her investigation while struggling with memory loss, the closer her life starts to resemble her novel until the line between reality and fiction starts to blur and she can no longer tell where her protagonist’s life ends and hers begins.