The Dragonfly Gambit by A.D. Sui

'Nearly ten years after Inez Kato sustained a career-ending injury during a military exercise gone awry, she lies, cheats, and seduces her way to the very top, to destroy the fleet that she was once a part of, even at the cost of her own life. Ennis Rezál, Third Daughter of the Rule, has six months left to live. She is desperate to end the twenty-year war she was birthed to fight. But when she brings Inez aboard the mothership, a chess game of manipulation and double-crossing begins to unfold, and the Rule doesn’t stand a chance.' --back cover.