How does one go about expressing "tired?" It isn't really a question of physical exhaustion, like maybe from working hard for many days on end. That's different. That's a feeling pretty much everyone can identify with. If they can't, well, not much you can do to help them.
This other "tired" though, is another story. Maybe sometimes it's best to just leave it alone then, if you can't describe it. Don't dignify it by giving it shape, or a voice. Just move through it.