I read it around 2002. The man lived in a community that was very old world and when he was infected with the nanobots it meant he would be killed. While escaping, his wife is killed. When he ran away he found a group of people that lived with nanotechnology where the people would work a certain number of years out of every 100 years depending on what job they did. He qualified for the most elite program, being a pilot of a space ship, but chose to go work on a space station at first. Eventually he went back and became a pilot.
It is "Gravity Dreams" by L.E. Modesitt Jr.
You can read it as an adventure tale, but the real subject is morality, ethics and a persons responsibility towards society and vice versa.
(That is actually true for most of Modesitt's work.)
From the back-cover:
In Earth's distant future, Tyndel is both teacher and mentor, a staunch devotee to his conservative and rigidly structured religious culture. Then a rogue infection of nanotechnology trasnforms him into a "demon", something more than human and he is forced into exile, fleeing to the more technologically advanced space-faring civilization that lies to the north, one that his own righteous people consider evil.
Although shaken by his transformation, he has the rare talent required to become a space pilot. What no one, least of Tyndel, expects, is his deep-space encounter with a vastly superior being -- perhaps with God.
"The space adventure side of the tale will be all that many readers want, and they will be thoroughly satisfied. Modesitt never fails on that level. But he is more than an adventure writer: He is also quite a thoughtful fellow and I found his musings on the need for responsibility in a high-tech society the more fascinating aspect of this novel." - Analog
This could be "The Days of Solomon Gursky" by Ian MacDonald;
- The protagonist is a Research Scientist, not a teacher
- His wife accidentally becomes infected with nanobots (and is resurrected by them)
- They live together in a reservation for "the dead"
- They eventually move offworld to live in space with the "freedead".
- Sol Gursky becomes a pilot (of sorts).
You can read a copyright friendly copy online here