There are twin factors that influence every aspect of your life - they are situations, and the way you deal with them.
The first is something over which you have no control, the second is something over which you have variable control.
The first is constant for everyone, the second is variable for everyone.
So people encounter situations, and deal with them in the way that allows them to assimilate the situations' effects into their lives, and live with them.
Because we are all unique, no two people are ever going to approach a given situation in the same way.
This means that some peoples' responses seem utterly alien to others - such as the forgiveness of actions by others.
So although i don't believe it is possible to 'switch those feelings off', I believe it is possible to treat them in such a way that they no longer occupy centre strage in an individual's existence.
Noit everyone can do this, but some can, and good luck to them.