Understanding the Black Flag Theory.

Everyone, at some point in their lives, has certainly raised the white flag to their enemies. Mature people tend to grow out of pointless fights and, having forgiven their offender, many times raise a friendly hand, only to get slapped in return.

There' s a solution, and it's simple. The Black Flag technique, also known as the "middle finger approach" is easy and straightforward. When they treat you like shit, and there's no shadow of doubt they don't want to treat you any better, BLACK FLAG.
Zero tolerance.

The basic idea is: I give a shit to you if you give a shit to me. If you're indifferent, that's cool too. But if you're mean, BLACK FLAG. I just won't try to make you like me. I will avoid any contact with you and mock you behind your back, just like you do to me. No more mr. nice guy. End.