There are many ways to calm a negative energy without suppressing or fighting it. You recognize it, you smile to it, and you invite something nicer to come up and replace it; you read some inspiring words, you listen to a piece of beautiful music, you go somewhere in nature, or you do some walking meditation.
Human beings are not our enemy. Our enemy is not the other person. Our enemy is the violence, ignorance, and injustice in us and in the other person. When we are armed with compassion and understanding, we fight not against other people, but against the tendency to invade, to dominate, and to exploit.
I would not look upon anger as something foreign to me that I have to fight... I have to deal with my anger with care, with love, with tenderness, with nonviolence.