Why did Hongmei leave at the end of the sea fog movie? Who was the last child and woman?

I like this movie very much. As usual, I read a lot of comments. Everyone has a clear discussion on the background of the event era, but I can't answer why Hongmei took this plot to upgrade the film by n grades. Tell me about my interpretation and welcome everyone to discuss. Smuggling is very dangerous, even fatal. For a woman, she has to endure being gathered among a large group of gentlemen and being robbed or xx from time to time. Two women who dare to take this road, one is an old woman who is well-informed and ready to "dedicate herself" .........