Some times, taking a enough rest also helps a lot in repairing the mental states, I have a ruin that I have maintained over the years and that is taking 2-3 hours daily to take rest during the day, this has helped me to charge up keeping me on a balanced mental state.
When you're tired and you don't have enough rest and sleep, that's affecting our brains and we can't think better when we're on that state.
It's true that taking enough rest is helping a lot, we're not machines, we're human beings that needs to get some rest. Well, even machines do need to even if they're designed to keep going.
That amount of rest you're taking during the day seems to be good enough and that's aside from the sleep that you get daily, right?