Broken — Robert J. Crane

Sienna Nealon is a broken human being. Her lover is dead, her closest friends have deserted her, and her employers have betrayed her. From the ashes of her desperation, she must master the metahuman powers at her command and finally tame the souls that share her body for one ultimate purpose - revenge against the ones who destroyed her life. Note: This is book six of the series and may not make sense to new readers. Book one is titled Alone, and is presently available for free in ebook formats.