What do we learn about Dell Duke's past in Chapters Five through Eight?

In Chapters Five through Eight, we learn that Dell once seemed to have had high ambitions for himself that never quite worked out the way he wanted them to. He doesn’t appear to have any family or friends, and the author clearly stayes that he never even had a farewell party when he left Walla Walla, Washington because no one cared that he was leaving. Dell seems to be content to get by with as little work and as little effort as possible... and he’s overweight, unkept, and lazy. In context, he just doesn't seem to care.