[TOMT] [book] [70s?] I only remember two character descriptions.

I'm trying to remember the name of a book that I remember next to nothing about. I only remember two character descriptions, and they are stuck in my mind.

First character I remember is a doctor. He is described as being a very nice older doctor. He was married to a woman who cheated on him. His dream was to retire early and work for free in a third world country. However once he "did the gentlemanly thing and gave her a divorce" she was granted alimony and he can no longer retire since he's obligated to pay her the large alimony. This makes me think the book is at least from the 70s or earlier, since the phrasing I remember makes it seem like he had the option to just not let her divorce him?

Second character I remember is a military officer, I believe a high ranking one. His wierd thing was that he never slept. He only power napped, and he felt this was way more efficient.

I think this book was a novel that took place during a fictional atomic war. So it almost certainly came out after the 40s. I think a lot of novels written about such a topic were written in the 50s and 60s. So that's my best guess, after the 40s and before the 80s for the publication window.