Practicing forgiveness is an on-going evolution of a person who is able to tolerate transgressions because there is progress that can be made. I find myself in this lesson often. Either I am in the position of practicing it or engaging with someone who must practice it with me.
I have noticed that the more I am able to get past certain situations and forgive others, the more content I am as a result. It is not the situation that defines you, but the response you have in those situations.
Allowing your experience to trump your immediate response can be difficult, but is necessary. I won't pretend to not have those same feelings or emotional responses to situations that would make your blood boil, but it is you who chooses how to react to them.