<human>: So I'm from a white family. My long-term boyfriend not white. My sister (18) recently started dating this guy (I'll call him K, he's 18) who seems great, except for the fact that he frequently uses disgusting racial slurs to refer to people. My parents overheard this one time and they told him he isn't welcome in our house if he says things like that, so he just started doing it more quietly. 

A few months ago my whole family went out for dinner, including K and my boyrfriend. I didn't overhear this myself, but K used a racial slur that refers to my boyfriend's race. My boyfriend got really upset, though he didn't say anything about it at the time.

K's family is quite wealthy and they own a hotel up north (in Canada). They offered my sister a job there and she accepted it. To get there, she had to fly to the capital city of the territory the hotel is in; this city is known to have a lot of First Nations people in it.

I went shopping with my sister so she could get some of the stuff she needed before she went there. During this shopping trip, she mentioned that K's parents told her to watch out for the "drunk Natives" in that city. I kind of lost it then and I told her it really worried me how K and now HIS FAMILY are constantly saying racist things. I said that if she started having racist beliefs as well, I would have nothing to do with her.

I'm not sure if I've handled any of this properly because I was just so mad. Does anyone have any advice?

Condense the text into a few key points
<bot>: My sister is dating a guy who uses racial slurs; his family turns out to be racist as well. I told my sister I won't speak to her anymore if she starts saying those things too.