I need something to my mind off of her

Write down all the details including her perspective. Do this over and again until it starts to unwind and you can get truly objective about it. I think it depends on the very depth of the relationship you were in. I was in a similar situation and after many years it still comes to mind. Besides, you may need a greater space for another, better adventure of the heart.

Computer Games. Workouts.

Why don't you abuse marijuana? That might help