The Forever Fight — Craig Robertson

Endless fighting. Hopeless odds. Then things got worse. Jon Ryan has beaten the odds so far. He saved humanity from a sinister alien threat and he stopped the insane android president of the United States three separate times. But the president won't stay dead and a super race threaten to end Jon's hopes for a peaceful future.
Jon's mind-boggling alien technology has been enough to keep everyone alive. But, just when there's reason for hope, a new, more deadly race sets it's sights on him. This threat may just be unstoppable. They made Jon fight. He plans to make them very sorry they did. Can Jon save humanity, his family, and himself when defeat looks absolutely certain?