Divided (Element Preservers) (Volume 3)

After spending some time on her own, Ria thinks she is ready to meet Oliver's group of magic disease carriers and find out what her brother really wants. But when her father reveals the secret that affects the whole world, she will have to make a series of decisions that could change her life forever.

Book 3 in the Element Preservers series. Young Adult Fantasy/Romance for mature teens.
Element Preservers series reading order:
DANGEROUS (Book 1)
RUNAWAY (Book 2)
DIVIDED (Book 3)
NO ONE (Book 3.5)
RESTLESS (Book 4)
INDESTRUCTIBLE (Book 5)