Lilith Mason Takes on the Everlore (Wretched Daugthers #2) by Wendolyn Baird:
 
Seek The Everlore and char the doors…

After surviving a haunting midsummer solstice, Lilith ventures into the depths of a city divided by the supernatural and dripping in secrets. There she’s met with the promise of archival grimoires… as long as she can survive the trials of reaching them.

The wrath of the fae has put a target on her back, and dark bargains have already wrecked lives she isn’t sure she can reclaim. But Beck is certain that Mairi and Castor have survived Death’s Knight, and Lilith refuses to disappoint him. With the grieving illusionist at her side, and a cynical palm reader dancing around her heart, she embraces the chaos of Penumbra.

Chronically ill and fighting against The Dahlias’ demands for perfection, it’s time for Lilith to make a choice. Will she give up everything she’s ever dreamed of for the sake of what’s right? Or will she finally put herself first and set the world on fire to save the woman she loves?