Never Enough — Lindsay McKenna

Novella sequel to Forged in Fire: When stunning Dara McKinley, a visiting pediatric physician, arrived in Afghanistan to help needy children, she had no idea that Delta Force Sergeant Matt Culver would not only win her heart--he would also save her life during an attack by the Taliban. Now, the couple is ready for a much-needed vacation in Hawaii, eager for days and nights of passion and relaxation. But once again danger stalks them. Dara knows she's in good hands with Matt beside her, but her fears rise again that she and Matt can lose each other as they face an unpredictable new enemy....