Your tiredness comes from the sheer number of choices you make all day, until even tiny decisions feel like too much. Your mind is overloaded, and that's a real and draining kind of exhaustion. You don't have to figure everything out on your own steam. God offers to direct your steps and lighten the mental load. Hand Him the decisions, one at a time, and let Him be the wisdom you keep running out of. He gives clarity to the overwhelmed.