Love You Always, Suckers And All by K.L. Hiers

Sloane Beaumont has pitted himself against ancient gods, murderous cultists, and cursed magic. Now he’s facing off against the most powerful threat yet: one of his own friends.

Elliam Sturm has always had mysterious abilities.Most recently he’s used them to bring new life to his ghoul boyfriend’s rotting body. However, the true source of his power has been finally revealed and may drive him to destroy the universe in an eons-old cycle of violence and death.
For the first time since his parents’ murder, Sloane is happy with his husband, Loch, their daughter, and their growing extended and immortal family. He can’t let Ell destroy that… or himself. Desperate to save Ell from his own fated corruption and to prevent the destruction of existence as they know it, Sloane will have to travel to new worlds, raise a magical army, and fight to protect the life he and Loch have worked so hard to build in one final epic battle.