Jennifer Ealey 
The Lost Forest [EPUB ebook] 

Caught in a blizzard, Prince Tarkyn and his companions get trapped in the Lost Forest: a mystical realm of captivity where all must face their innermost fears — or spend an eternity. 
The challenge fractures Tarkyn’s friendship with the woodfolk at a time when he most needs their allegiance. As the enchanted realm’s true purpose unravels, Tarkyn’s brothers — King Kosar and Prince Jarand — prepare their armies for war.
As the turmoil threatens his friendships and a warning from the Forest Guardians reveals a deadly threat, will Tarkyn be able to repair the deadly rift destroying his kin — sorcerer and woodfolk alike?