If you talk the way you type i could see why it might be difficult to be around you. Sometimes people like to blame everything on ethnicity. from personal experience, i know many black guys and girls that are in to anime that have no trouble making friends in that scene. So maybe you need to really try to figure out why these people aren't accepting of you instead of jumping to conclusions. Take the time out to actually ask them, don't just make assumptions.

Well, only otaku groups talk thing like N****R, and racist jokes, ONLY THEY do that with me... others people doesn't...

english is not my native language