Hi I would believe that the ending is indeterminate. It's hard to conclude whether the author was aiming for a happy or sad ending. It's should be more based on your own opinion of the way the story played out and from that you should form your own conclusion for the ending.

As for the plausibility of the characters, it certainly is plausible, however the author could be writing the story as an exaggeration of the time period. In the end I think it all comes down to your own opinions since stories are meant to be interpreted by the reader. Just my 2 cents.

This page  http://www.hwkhelp.com/node/130 provides a good synopsis and character analysis of the story.