Am I missing something or does the game just end with the grave stone admonishing you for not turning back?
Yeah, in general trying to philosophise about something you're actively encouraging players to do as a part of the challenge and fun of the game, and in general *punishing* players for engaging with your produce, never works out. Unless of course, you make it quite tongue in cheek - like
~It's a shame the hero could never look back~
~~Now he's trapped forevermore~~
~~~(psst that's the end guys! thanks for playing)~~~
Which makes it clear.