Showing Her Forbidden Hero by Laura Kaye

Former Army Special Forces Sgt. Marco Vieri has never thought of Alyssa Scott as more than his best friend's little sister, but her return home changes that...and challenges him to keep his war-borne demons at bay. Marco's not the same person he was back when he protected Alyssa from her abusive father, and he's not about to let her see the mess he's become.

...but now she's all grown up.

When Alyssa takes a job at the bar where Marco works, her carefree smiles wreak havoc on his resolve to bury his feelings. How can he protect her when he can't stop thinking about her in his bed? But Alyssa's not looking for protection--not anymore. Now that she's back in his life, she's determined to heal her forbidden hero, one touch at a time...