Back in N'Djamena, Omar says he has no regrets.
"I miss my family but our life is comfortable. We have our house, some land.
"My one big wish is for my children to go to school. Just to register costs 20,000 CFA ($40) per child, and then there are fees, books and uniforms.
"One day maybe I can pay for one or two to be educated."
Words and pictures: Stephanie Hancock