Vicious by Lindsey R. Loucks

Absidy Jones, a fugitive ghost magnet on the run for two murders she didn’t commit, desperately needs to warn the human race. The Saelis aliens are coming to finish a two-hundred-year-old war and decimate the rest of humanity.
No small feat for Absidy, especially since she and her spaceship’s crew are stuck in deep space.
Pasts collide on the once-haunted ship she now calls home, leaving the crew stranded with no outside communication. Murder, secrets, and betrayal lurk around every corner, more vicious than anyone thought possible.
Startling discoveries force Absidy to risk the lives of those she loves to save all humans, even as her special ghostly gift seems to be…evolving.