The girlfriend is mixed race, and feels a need to promote a ghetto attitude, and regularly associate with black people on Instagram and such. Dude gets angry with this, not due to the fact that they're black, but that she feels she has an image to uphold, and feels the need to put up a false persona of herself. Girl has been criticized in the past for being a wannabe hood rat, and he seems to be trying to protect her from the haters.
"I don't want you to have to hate. That's what people do- they turn things around. I want you to love them- privately. In your whole life, everyday you can be with them. Every single day of your life. But you don't have to promote it, like you're trying to prove something."
His problem seems to be not with black people, but a select group of people that he believes are a bad influence.
The main quote is rather misleading, all he said was to not bring 'them' to my games, referencing the certain friends, while his girlfriend was the one to actually suggest 'black people' as an answer, to which he didn't respond.