Sometimes erasing a memory can be as easy as pressing the Delete button.........Its easier that way! Carrying accessive emotional baggage gets you nowhere! So have selective memory - keep the control panel in your hands- You have to decide what you want to feel nostalgic about (If you want to that is).
Switch your thought flow to something much more important and fruitful but definitely not related to your painful memory. Afterall Ignorance is Bliss!
This way you spare yourself of a lasting trauma. And always remember its best to let go when you know there's no hope.