Back in January, I wrote about Gaston from Beauty and the Beast, and people are still interested in the topic.
Reading people's comments have caused me to think about another moment in the movie: the ending, where Gaston fights with the Beast. If I recall correctly, the Beast and Gaston have never seen each other before the fight. In fact, the Beast has no idea who Gaston is at all. He's just fighting for self-preservation.
Why is Gaston fighting? I'm not entirely convinced that his motivations have anything to do with Belle. You could argue he's trying to impress her, or you could argue that he's being a jealous ex-boyfriend who thinks, "If I can't have her, no one can!" But really, I think Gaston's reason for fighting the Beast is more about himself than it is about Belle.
Gaston is basically fighting the Beast, in order to help his bruised ego. After all, he's supposed to be famous and well-loved for being a master hunter. But then his ego and reputation took a huge blow when Belle turned down his marriage proposal, in front of the entire town. I mean, thinking about it. The best-looking girl in town just dumped him before they were even together, and everybody was watching.
And that's why Gaston decides to go after the Beast. He feels like it will save his reputation; if he kills the mythical monster, it will "prove" that he's not a loser. Gaston manipulates the townspeople into forming an angry mob not because he wants backup, but because he wants lots of people there to witness his heroic victory over a foul monster.
I'm relatively sure that Gaston has no idea the Beast used to be a human. The Beast says a few things to Gaston, but it doesn't seem to register with Gaston that the Beast is a talking, thinking human being.
Anyway, that's just some amateur psychoanalysis on Gaston. I think I'm saying that his actions towards the end boil down to the fact that he only cares about himself and looking good in front of others.