I am having difficulty in identifying the main themes in the book Fat City, written by Leonard Gardner.
What is the main idea in the book Fat City?
Is it about the fighters' lives or about how bad relationship could ruin one person's dream?
The story Fat City, by Leonard Gardner, presents important, universal themes. I believe those you have identified both fit into the message the author is attempting to convey to the reader.
Fat City concentrates on two boxers who want to experience success in the boxing ring, and bring that success into their personal lives. Billy Tully is closer to the end of a boxing career, while Ernie Munger is just getting started.
Both men are presented with solid opportunities to make themselves a name in boxing. The similarities in the two men are the things that ultimately get in the path to their success. Both Billy and Ernie lack the focus and commitment to filter out life's distractions and pursue their dreams with pure passion.
Instead, they allow those "distractions" to derail their progress. Tully's life quickly falls into ruin, and besides losing his dream of boxing, he loses, too, the opportunity to make amends to his wife and start fresh. Similarly, and unfortunately, by the end of the story, iMunger, even so young, with so much potential and promise, is taking the same self-destructive path as Billy has taken.
The themes I see here are:
...that life cannot come to you: you must meet life head-on. And it must be done with complete dedication and unwavering motivation. Everyone experiences obstacles, disappointments and heartaches, but many people are so committed, that nothing can stand in their way.
[Overall, the] message...from Gardner's book is that one must be truly dedicated to one's purpose in order to achieve it, and avoid those things or individuals that people sometimes invite into their lives that bring with them failure and loss of hope.
I hope this is of some help.