Hey, the Meridian Republic did have people who started it with the intention that those lands ravaged by the monsters could be saved through human cunning and diplomacy rather than brute force -- of course the RoF remnants who joined it clearly wanted to restore themselves to their former position.
I got out of it because, from an RP perspective, my character felt incredibly betrayed by the course of events from there... and once again for anyone saying that MR was particularly opportunistic, I must only point your gaze over to the actions of Enweil, Avalon and Bara'Khur, who expended most of their resources trying to attack the newly forged Republic along with the daimons, and frustrate the losing battle that Hetland had against the invaders.
You had a Lefanis. Who was contanstly trying to get Rio to ally the monsters against Enweil.
If that wasn't enough, you also had a bunch of nobles who had refused to ally with Enweil against the monsters, preferring an alliance with the monsters.
To then move your capital to an Enweilian city.
With the plan of expanding your realm, as per the deal with the monsters, into Avalon's lands.
Expanding in the wake of the monsters' army.
That you fed with your own peasants.
In the process, recreating a realm we were all happy to have exterminated.
Now, can you think of one good reason why we wouldn't have declared war on MR?