The lightheartedness at times is somewhat at odd at times with the general content and theme of the story. Her heroin is a rather frisky lady who spends alot of time discussing her husbands private parts, her name for these private parts, and much of the usual newly wed baby talk that only newlywed couples enjoy. All of this is at least on point with the books major therme.
The major theme of the novel is that happiness is found within. If you have the bare necessities, and people around you that you love, you have the minimum requirements for happiness. If you have those items, and you are not happy, the problem may not be your circumstances, but yourself.
When I was kid I used to like reading sci-fi novels, some of which painted very bleak and depressing scenarios of the future. But this was not how I'd ever imagined the future. And anyway, I wasn't the future. It was the present.
Besides like I said, all things considered, it really wasn't that bad. Nor for us. At least Aaron and I were together. That was the main thing.
They eventually make a trip from Central Florida to their native Buffalo, New York. The few areas in reasonable condition are under martial law. The noted "Aaron" is a general practitioner, so is not likely to be left starving, but most people are subsisting on government handouts. Electricity is available, but only at great cost, and gasoline is almost unseen. Vehicles that can run on diesel-cooking oil are about the only thing that can keep going: and even there on a very limited basis.
In summation, it is a rather nice, a bit light hearted, apocolyptic transition novel. The idea that joy and satisfaction are not within your circumstances, but within you, is a very compelling one that more novels of this type should probably remember.