In the same way that the proletariat was first defined by the capitalist oppressors but then self actualized and grew into an independant identity based off of their experience and work and the capitalists remain defined by their oppression of the working classes.
So too was blackness defined by white supremacists, but through our experience, through our work and our humanity and our love we have gained an identity independent of whiteness, while those who claim whiteness are still defined by supremacy.
Blackness can exist on its own, but whiteness can not.
So celebrate with your comrades who celebrate their blackness, and shed any kinship you have with the oppressive identity of whiteness and the evil supremacy that it always carries.