Rage of Her Ravens by Tara West

She seeks solace. They want vengeance. How can she save the world while consumed by the fire?
My life has become a shell of the one I once knew after losing my other half, my dear twin sister. Before she was killed in a bear attack, I made her two promises, to raise her twin daughters as if they were my own and to protect them with my life. Until now, I’ve kept those promises.
When the wicked Fae Queen Malvolia sends three winged fire mages to hunt us, I’m faced with an impossible choice, kill them or let them take us hostage. Killing them would be too easy, for I’m gifted with the white magic of the siren’s call, and with my powerful voice, I can bring entire armies to their knees and watch while they slit their own throats. Unfortunately, these mages are my fated mates, tasked to coerce me to join Malvolia’s army.
And there’s one more problem. Rumors are circulating that my twin is not dead, that she’s grown into a powerful white witch, and she’s marching with Malvolia’s enemy to destroy us.