Micro God by K.R. Martin

Richard Clarke is a man born with the unnatural ability to control all reality around himself. Whether it be granting himself immortality, stopping bullets in mid-air, or destroying his enemies with a mere thought, he is often feared as a god on Earth. However, outliving everyone he ever loved whilst losing friends to the limitations of his powers causes a heavy burden upon his shoulders, and in the 21st Century, Clarke is a stoic loner, traveling and living only to kill evil. He has no time for friends or family, but all that changes when he meets a dedicated doctor working in the dark streets of Detroit. "That which is destroyed cannot be repaired. That which is mended cannot be maintained."