Just a vent

Hi, idk where else to post this but I wanted to vent about this. So there's this coworker at work (who's white) who always feels like mentioning that I'm "only half-black" when I say something about being black. He always says it as a joke, but I still feel some type of way about it. He started saying it when I was mentioning celebrating BHM and stuff. And then I mentioned to my siblings that it bothered me, and they told me I was taking it too seriously. In fact, my sister took his side entirely because she likes the guy 🤦‍♀️And then I was talking about how the people at work in general seem comfortable making race jokes (for reference, the place we work at is majority white). Like this one time this kid was making jokes about saying the n-word. And my siblings said it's just a word, it doesn't mean anything, which completely makes no sense to me. And also I pointed out that a manager completely encouraged a white coworker to report racism against white people, but when I tried to report something, it was just brushed off and forgotten. And I've heard them complaining about how white jokes are racist, but black jokes are completely okay to them for some reason. I just wanna know if I'm overreacting or something because my siblings believe I'm looking too deep into it.