The Ascendant Wars: Brimstone: A Military Sci-fi Series

The Ascendant Humans have conquered Earth and banished mankind to a distant star. There, the refugees war in space over the resources rationed to them. In an orbital habitat, Commander Rylan Shaw labors against the inter-colony arms trafficking when an informant gives him horrific news. The ruthless
cartel boss, Lilith, has stockpiled weapons of mass destruction. Worse, she has permission from the Wardens, humanity's robot overlords, to unleash them upon the system.
As the battleship Infinity speeds to investigate Rylan's discovery, her operations officer, Scott Carrick, soon finds himself in a trap more deadly than he could have ever imagined. To his dismay, he learns that his only hope of escape may lie with their most junior crewmember, a gentle nurse named Aila Omura.
As Rylan, Scott, and Aila struggle to survive a war where the rules keep changing, they must answer a terrible question: how do they win when it seems the Wardens intend for everyone to lose?