I totally understand. Sometimes the tragic end really is the right one. I’ve got more than one novel cooking involving incest and even I have one or two that end badly/tragically.
But then I also understand how attached you are to them, and you don’t want to kill them.
I can’t help but I can sympathize!
Don’t know if you’ll see this, but just a comment to the anon: The fact that you even feel empathy for the characters says that you are not making the decision for the sake of appeasing negative people in society. It shows you are an artist who is true to their art. Tragic endings are as valid as anything else and if you are fair in the way you write characters in general, that honesty will show to those who can see it. Do what you need to do ^_^ In creative writing class, one of the most valuable lessons I learned is that whatever decisions you make for your story… the most important questions should be: Does it work? And is it Earned? (and by that I mean have you given the appropriate build-up towards the ending to make it a believable/plausible outcome?)