Heaven (Book 3) by Alexandra Adornetto

Bethany, an angel sent to Earth, and her mortal boyfriend, Xavier, have been to Hell and back. But now their love will be put to its highest test yet, as they defy Heavenly law and marry. They don't tell Beth's archangel siblings, Gabriel and Ivy, but the angels know soon enough, and punishment comes in a terrifying form: the Sevens, who are rogue angels bent on keeping Beth and Xavier apart, destroying Gabriel and Ivy, and darkening angelic power in the heavens.

The only way Bethany and can elude the Sevens is to hide in the open, and blend in with other mortals their own age. Gabriel and Ivy set them up at college, where they can't reveal their relationship, and where there is still danger around each corner. Will Bethany be called back to Heaven – forever – and face leaving the love of her life?