Wait 24 hours before getting mad and reacting about anything. If it doesn’t bother you in 24 hours time, it probably isn’t important enough to get mad over. This is some good relationship advice whether it be for romantic or friendly relationships.
Learning to Ignore things is one of the great paths to inner peace. It's also one of the most fascinating path to evil. Just ignore your conscience, just ignore that voice that tells you that what you are doing is wrong.