[Sage]

Good for him!
His wife might not be divorcing him for the reason you think, though. There is a syndrome where a person wants to have someone totally dependent on them, and one of the easiest ways to indulge this syndrome is by feeding a mate or child until they're unable to leave the house or take care of themselves. That's how these "Jerry Springer" favorites who weigh absurd amounts and haven't been out of bed in years get into the state they're in...if they're eating a carton of eggs every morning for breakfast, someone has to be feeding them.
By taking the walk to lose weight, the man in the story attempted to break away from this syndrome.