The Shadowbound and the False God by Fern A. Ellis

The Red Woman was made. Now, she must rise.

Aisling Morrow moves through her life like a ghost, forever changed by the events that led to the reawakening of the long-dormant Silver Saints. She’s seen the corruption of power and has borne the heavy weight of prophecy. Now, beset by guilt and frightened by the decisions she made in the name of peace, she must gather what remains of her strength to journey alongside Rodney, Raif, and Lyre into the god realm to find the Unseelie King.
But Elowas is a dark and twisted place, one that was hewn from shadow and poisoned by depravity. And the entity that awaits Aisling there—the eldritch god that spirited Kael away—is even more terrific than anyone imagined. He has staked his claim over the king and the power that binds him to both realms, and with that power would see a return to days of old when the Wyldraíocht Fae worshipped him unreservedly—and humans paid their toll in blood.
Amidst the realm’s decay, Aisling learns of bygone deities, the sacrifice of the Silver Saints, and a magic long since lost to time. The tale of Elowas and those trapped there is a sordid one, and recovering what was lost will push the rescue party to the limits of their resolve as they fight to escape the nightmare themselves.

A human woman, a warrior, a Weaver, a worshipper, and a once-powerful king will discover that in a realm blackened and broken, only one certainty remains: fate is not quite through with the Red Woman yet.