Aeon War by Amelia Wilson

Sarah has been thrust into a galaxy spanning war, where she has found herself to be the only hope for a race of aliens on the verge of total destruction.
Sarah is from Earth, but she hasn’t been there for months. She’s found a friend and lover in Gar, and handsome Zaytarian who has helped her out of more scrapes and dangerous situations than she can remember.

The Aeon’s are a psychic race of aliens who thrive on domination and driving other species to extinction, and they have their sights set on the Zaytarian’s. The only hope Gar and his people have is a small crystal Sarah has worn around her neck since childhood, a gift from her Geologist father. The crystal is the key to a doomsday weapon, one the Aeon’s hope to use soon. But under Sarah’s guidance, the key might be able to destroy the weapon, and the threat of Aeon rule for good.

Will Sarah and Gar reach the weapon in time? Can anything stop the Aeon threat? And when it’s all over, is Sarah ever going to be able to leave the alien she’s fallen for, and return to Earth so she can lead a normal life?