<human>: Using a throwaway since she is a redditor.

Yesterday, my girlfriend and I were talking about what costumes to wear for a halloween party. She quickly decided she would be a victorian noble lady (she has a dress like that laying around from a party a few years ago), I had no idea what costume to wear.

At this point my girlfiend half-jokingly tells me to "dress up like that spear-chucker from Diablo because you kinda look like him". She is referring to the Witch-Doctor class in Diablo 3 (which we both play). I found that to be pretty hurtful, considering I am African-American. She is white, for the record. 
I told her my feelings were hurt by her using those kinds of slurs towards me, but for some reason she just laughed it off and said I was being ridiculous, and that she simply meant that, because both me and the character were black I should dress up like him since it would be easy. In my mind this just made things worse, but she didn't want to talk about it anymore and went to bed.

We haven't talked about it since, since when I bring it up she says she is tired or "doesn't want to deal with it" right that moment. When I pressed the issue, she told me to stop whining so much and left the room. 

At this point, I am not sure how to handle this. I love my girlfriend but at the same time, her ignorance around this and her unwillingness to discuss it makes me think that something is terribly wrong in our relationship.

Give me a shortened version of the text
<bot>: White girlfriend refers to me (and black people in general) as 'spear-chucker', doesn't want to discuss how this is hurtful to me (Black).