If the ending of ROCH had Yang Guo still waiting for Dragon Girl after 16 years it is still open ended and i would conclude to myself that there is hope and one day they will be reunited. The difference would be that i would respect him more for staying faithful despite the uncertainty.
I already get the impression he separated them to begin with because she was raped and he has sexist attitudes towards women and felt the need to punish that couple for something that was not their fault.
The best thing about ROCH was that Yang Guo was willing to defy everyone for the one he loved and did not care she was raped. It woulda been really boring if he was like Guo Jing in his role as protagonist and being a cookie cutter hero. I like the way he was able to do some good for the country but in the end his first priority was the woman he loved - there are far too many stories where heroes sacrifice their love for their ambition or the greater good.
Perhaps when i finds stories where ppl have suffered enough and the ending is open i tend to construct a more positive ending to make it more palatable for myself. Like in The Age of Innocence i like to think that Newland Archer did not see the woman he pined for after more than 16 years because he finally came to understand why he longed so much for her - i don't think i can handle that story if he came out at the end no wiser than at the start. In that case though the more i think of the open ending the more i like it because there is just so many ways you can interpret why he did what he did at the end.