The Stars of Redemption. Genesis Earth Trilogy, #3

The ultimate redemption can only be gained after you confront the past. When the scientists at Heinlein Station punched a wormhole through the stars, they created a temporal paradox with dire ramifications for the future of humanity. Now, Estee and Khalil are trapped in the product of that paradox: an ancient, alien ghost ship that has wandered the stars for millions of years, biding its time for the final day of reckoning.
Her family broken and her homeworld shattered, Estee struggles to care for her younger sisters as they search for a way back home. But Khalil carries wounds of his own. He blames himself for the loss of his platoon, and wants nothing so much as to end the pain-even if it means becoming a martyr. Only Estee and Khalil can stop the ghost ship from unleashing its devastation. Temporal paradoxes are never quite so simple, but fortunately, there is always a path to redemption.