I watched the last two episodes, not having seen any others. So, I started watching from the beginning. I'm in season 3. It's obvious that Daenerys was nuts from the start. She's clearly in the crazy zone on the hot-crazy matrix.
It's also clear the Daenerys and Cersei could not co-exist. Mutual assured destruction awaits them. With tough men out of the way, the women are leading the world to armageddon.