The sheriff did not fall in love with the widow because of the promise of "live as long as he wanted", but he fell in love with the widow, so he tolerated her behaviors that were unacceptable to many men.
In the western part of the country at that time, it was like an animal world, where the weak preyed on the strong, and the best choice for everyone was to become the strong or the weak dependent on the strong. The widow is like this, everyone in the town is like this. As the prostitute said: Love is extravagant. In that environment, romance must first obey to survive.
Like other western films, there is a deep brotherhood that is attractive. But friendship can only help the immediate favor.
All in all, it is a sad and true West, and no ideals, justice, love, and friendship can be strong.
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