I know it's hard for all three of them but cheating has to be the last option. Not all people who get cheated on can find love again, after all those trust issues and trauma. I am happy for Natsuro. He found a better person that deserves him. 
I love all Ueda Aki's stories but this one is my least favourite. I am glad I read Natsuro's story first. At least I know he will finally be happy.
