Every now and then I see posts from people actively omitting my name and editing history in a way to remove my presence. These are the same I called them friends, used to hangout, share meals and work together.

I still have no clue what motivates them and lead to such active actions.

It further enrages to see others who know it all, were present then, and now just see all this, choose to ignore. What makes them not correct such behaviour when they can do so?