D.M. Cain 
Genesis Of Light [EPUB ebook] 

Warring countries, fantastical creatures, beings of terrible power and journeys of epic scale. The legendary Book of Alcherys tells wild and unimaginable stories. But they are not mere fairy tales. They are true, every word.
Callista Nienna is strong and independent, but nothing could have prepared her for civilization being brought to a violent end. Now, she is forced to stay alive in a desolate wilderness with only her closest friend for support.
She has two choices: give up and die with the wilting world around her, or seize her destiny and make it to the only sanctuary left unscathed. At the end of her journey, something awaits Callista. Something both terrifying and unbelievable.