I liked this more than most of the other reviewers. In my mind it is a simple case of a short man (5'7") who has always felt challenged because of his below average height. This rings true with me because I grew up with a similar friend. He did anything he could to compensate, even telling me at age 12 that he would marry a woman much taller than himself, so none of his children would be as short as he was. He did marry a woman 8 inches taller than he was.
In this story there are no sympathetic characters, the little man, the tall man and the wife are all unlikable. In my opinion, this enhances the story, I don't always need to relate or like a character to enjoy a story.
SPOILER: In the case of the story, the little man (mentally and actually) decides he must win at any cost. Of course, he defines winning as he wishes, not to win back his wife, but to hurt the tall man, even if it means his own death.