Uncertainty asks the mind to solve something it cannot yet solve. So the mind circles, rehearses and plans, and we grow tired without moving anywhere.
Mindfulness offers a smaller question: what is actually here, right now? The weight of your body in the chair. The sound in the room. One breath, then the next.
This is not avoidance. It is choosing to spend your energy where it can be useful, instead of on a future that has not arrived.
When the circling starts again — and it will — you simply notice, and come back. That returning is the practice.