Why do I exhaust myself trying to control outcomes at work?

You are wearing yourself out chasing outcomes that were never actually in your hands, the client's decision, the market, the way others react. It feels responsible, even necessary. But much of that effort is spent pushing on things that do not move for you, and that is why you end each day so drained. Here is the freeing truth: you are responsible for your effort, your judgment, your care, not for the result those things produce. The result depends on a hundred factors you do not command. When you tie your peace to outcomes, you hand your peace to forces outside yourself, and they will never hand it back. Start separating the two. For your next big task, write down what part is genuinely yours to control and what part is not. Pour yourself fully into the first. Then, as best you can, let the second go. You will do better work and carry far less weight, because you will finally be spending your energy where it actually lands.