Looking for a story about a soldier from around 1990 to the 2000's. It was about a soldier that came home from a war and didn't fit in. so the army offered him a deal. He was to go into some sort of hibernation and be revived when need of his talents was needed. Him and his fellow soldiers would earn pay while asleep. He is awakened to fight a few years later and he was offered the same deal to do it again. The next time he awakens to fight he realizes the world is much changed. this goes on for a few cycles and then he finds out his pay has been taken while he was asleep by the government. So he continues to cold sleep between battles. Eventually a device is invented that allows him to be stored electronically After that he keeps fighting, and if he dies they make another copy to fight. He retains his memory and skills. Eventually they try using multiple copies to fight at the same time. This goes on for centuries. The end of the book is with him trying to destroy the device that contains his imprint.
Found it! Its called "The Eternity Brigade" by Stephen Goldin
This is a story of young men whose bodies are reconstructed to fight war after war after war centuries, even millennia, into the future. Dying in battle is illusory, because they'll just be reincarnated to fight again, bleed again, and perhaps die again. And it's the story of how one man manages to cheat the system.
This sounds like To Sing of Chaos and Eternal Night by Lucas Bale.
A soldier trapped in an endless war dies over and over, only to be awakened each time to fight again – one of the last remaining few seeking to save mankind from extinction.