Hi OP - I am in a multicultural relationship, though the dynamics are slighly different to yours. I am white (male) and my partner and her daughter ( who I adore and regard as my stepdaughter, even though legally she isn't!) are Tanzanian. I have to say that, although we are in an area of the UK which could not be regarded as particularly diverse, we have never been subject to any open comments or hostility, but the odd raised eyebrow has not gone unoticed! However, we care not a jot as we are a strong family unit, feel, as you do, that who you love is who you love, regardless of their cultural, religious, or racial background. These, of course, are only our own personal experiences and I cannot second guess the reactions we might receive were we to have children together - that might be a different scenario, but, once again, we would not lose too much sleep over it.
That is not to say that I will ignore racism in any way, shape or form. Far from it - I have an ongoing issue at work with a 'colleague' who has shown open hostility and made vile, abhorrent rascist remarks about another member of staff. This is being dealt with, the police are involved too, as it is a racially aggravated hate crime and I am going to persue it, even if it costs me my job.
I think what I am trying to say is that my family and I just try to get on with our lives, regardless of what others may think - after all 'only dead fish go with the flow'.
Good luck, stay strong, ignore those with no cognitive ability or narrow minds!