This is one of the various ways people react to unfavorable environment in their day to day life when they believe that nothing they do can change the environs to a favorable state. It is a process. When the weather is inclement one tries to acclimatize. Voluntarily and involuntarily as well. When that becomes impossible beyond a point and things are still not tolerable and leaving the environs is unlikely you try to ignore it. One ignores it that well when subconsciously it doesn’t exist. It could be called denial. That is the state of your mind if you have come to believe that racism doesn’t exist and it exists in the victim’s mind or only in the interpretation of a person who calls himself a victim. Denial. As I recall Nevillle Chamberlain the former British Prime Minister was a famous exponent of the practice.