Esta has mostly been trying to blank out his mind until the next time he sleeps. It is what he'd do if he'd been tortured, and had managed to schedule himself to not need to do anything else of importance or significant effort that day. When your mind has taken a huge hit, you will not be all better the next day after sleeping, you will not be all right, but your mind will have gone a little closer to equilibrium, if you can delay thinking until then.
The thought that he could not seem to suppress is wondering what comes next in the Outer God's plan, and if it was considered important to It that Esta lose his connection to Asmodeus.
But he has managed not to think any thoughts after that thought, about what specifically might be planned.
