I like to think that Riza had been Roy's eyes for all this time, to see more possibilities and to never lose sight of what's important. In a way loosing his sight for a while made him see things more clearly on how to be a better person.
@_mayaamano I remember the first time I played p2ep after beating nyarlathotep I accidentally choose the option that leads to that kiss, I was so disgusted I closed the game and replayed the last battle to get the right choice
after re-reading the first chapters of fma i've come to think of how tragic was Nina's death, It initially served as a device to show how horrid alchemy can be, followed then by the revelation about the philosopher stone real nature