Mercy and Starlight by Bridgette Valentine

For the last year, both the earth and fae realms have been cursed with a botanical plague known as The Becoming. The old gods have abandoned them and leave no trace that The Ether ever existed.
Mercy Brittlemore’s reality as a mage’s apprentice consists of concocting potions, ripping vines out of men, and toying with fae tavern folk just to feel something. Between nursing a catatonic princess back to health and contracting The Becoming herself, Mercy’s life is already a whirlwind when she’s thrown into an enchanted portal to the celestial realm.
Trapped in The Ether, Mercy’s luck is tested when she’s offered sanctuary by the high fae lord, Evander. An idyllic kingdom with lavender moons, extravagant balls, and swans who transform into princesses.

With her feelings for Evander growing daily while her condition worsens, Mercy is forced to face herself and find a way home.But when she gets there, will she find her old self?