Twilight of Darkness

There's something wrong with this rating system. You fulfill their requests, increase your rating, and suddenly, with 40% trust, they declare war on you. I thought it was random, so I replayed the turn. Same thing happened. Meanwhile, the other two factions have a -30% rating, and they're at peace. I didn't even see the Elves when they declared war. I think there should be some logic in the AI's actions regarding the rating. Otherwise, it's useless – just kill everyone.