Hello girdhar: I see this is your first post here on PC. Welcome to Psych Central.

I'm sorry but there is no way I am aware of to erase a memory. In fact, the reality is, I believe, the more you try to rid yourself of a difficult or painful memory, the stronger it becomes. The key is to learn to be able to simply allow the memories to arise & fade at their own pace without becoming hooked by them. Here are links to 5 articles, from Psych Central's archives, however that offer suggestions for how to cope with difficult or painful memories:

Coping with Obsessive Thoughts

Why Can't I Shut Off My Mind?

Eight Step Method for Managing Intense Emotion

7 Steps to Conquer a Painful Emotion

9 Ways to Let Go of Stuck Thoughts

I hope you find PC to be of benefit.