The war was a secret from everyone who wasn't involved during the first war and transitioning into the second war. It was confirmed it wasn't an open subject in one of the blogs IM STILL ALIVE uploaded, even saying:

"There's a bit of a story behind what's happening and why. I'll tell you ONLY if you decide to help fight what's happening".

It was kept a secret for so long because of the paranoia stage. It was assumed everyone was unable to be trusted, even the best of friends. The conflicting information that was told, the ones regarding the people around, even the ones that we assume are friends, might not be who they say they are. 

So, in order to avoid more problems, the war, even Wikia itself was kept a secret from everyone. It was no longer brought into conversation, help was no longer sought after. It was left to make do with what was had and what would be left, no matter what may have been lost.

Keeping it a secret was also to hopefully prevent more people getting hurt or prevent bigger conflict. The isolation was thought to finally make the war die down. But, now we all know that was a mistake.