How do I get it through to my sister that she's racist?

oh hun you can never get threw to people like that lol. i noticed when someone has to point out they have black friends they are usualy racist or when they tell a black person that they dont have a problem with black people they are usualy racist cause normal people dont have the need to say that lol. like my sister is racist but yet she claims she isnt cause she has black friends witch may i mind you sh talks about when arnt around. she even sat around calling my kids tido and toby (if you know nything about black history this is very rude) and my husband a n**** (even though hes dominican not black but shes stupid and doesnt know the difference) but yet claims shes not racist. its a new type of racism now its hard to explain but people know its wrong so they let it come out in little ways. im sorry but she will never admit to being a racist unless she feel you are on her side maybe you can get her to believe you dont like black people either in order to get her to confess she doesnt either record this so you can show her. if you dont show her she will believe it never happened and will still never admit it. thats the only thing i can think to tell you but even that she will start making excuses. good luck though