An SO will align their goals with you. A best friend may find another goal in life and go off on their own. A friend isn’t tied to you, and you’d support them if they ‘leave’ you to seek their own fortune. A partner stays with you and you and they need to find ways to reach your goals together. There’s a stability and security to a partner that you don’t get, no matter how close your friend is.
Short of wearing a white fleece with bright pink hearts on it, nothing.
Because your face isn’t threatening.
The people being threatened by you, are being threatened by their racism, and that’s not your fault.
Keep living your best life, and keep proving them wrong. They’ll figure it out eventually, one by one.