Do you have a good grasp of the shift key animations in this game? If you give your guy decent agility and speed, turning around should be instantaneous. You just need to make that pivot early to match the speed of the guy bearing down on you.
The big thing playing D in this staying in front of a puck carrier. The moment his stick crosses your body, he loses possession. Even if you have your back to him.
Also, if you're 'stopping dead in your tracks', you're the one who's stopping, not the game. If your guy has momentum, you can make that pivot and not lose any of your speed.