I know this feeling all too well... All of the unanswered questions... They haunt me everyday of my life. What if, what if, what if, what if...
I wish I could tell you something that could take all the pain away, but unfortunately closure only exists in fairy-tales.
However, I can offer you one piece of advice that keeps me going:
You can choose to succumb to the dark spiral that is ptsd. No one can judge you on that.
Or... you can take all the terror, the corruption, the fear that you have bottled internally and transform all that energy into something equally powerful and just. Fight for that last shred of goodness you see on Earth, if not for you, than for those you love.
Instead of being reminded of the past, try to see the girl as a second chance. A chance to fight for her and all the other innocent people taken from this world.
You still have the chance.
Good luck my friend, you are not alone.
-ZRT