In real life there is no pure evil. If you winner - your are Good One.

"Winners are not judged" (c) Ekaterina II.
So if you are trying to project your real life experience on fantasy game world you will always fail.
Comparing to real world Fortress and Empire equaly evil. All they do is destruction. Difference that Fortress do that "While helping others" and Empire "While helping themselves". Compring to real world it is just a difference in motto, banner and crest.

Anyway it is normal to roleplay lightwalker who have doubts about righteousness of his way. I had one and it was even empowered. And my doubts that I'm doing right was part of his role. And he was not sure that slaying of dark ones is the way to bring light. Sometimes he was sure that mercilless slaying of "red auras" increase darkness in this world.

And he was ok. No he was not in fortress. He was deleted at 35, because had no time to play.