baby 2011, my ds is a teenager now and I would wish you not to take too much of this to heart if you can help it. I did massively but it was to my detriment.
I think as parents we all have to develop not only a much thicker skin but a realisation that there is often some way we can feel left/out unincluded.
I joined an NCT group with dd and they were all much younger and wealthier and I ended up feeling so inadequate that I sort of let them go.
ds had a few parties in church halls where we invited everyone. But I remember so well that a boy who came to all ds's parties and for a play date once. eventually had a party and invited everyone but ds. I was devastated. I felt so hurt, it was as if she'd stabbed me in the street and spat in my face. Very irrational for sure but profoundly felt.
Now i don't have the racial experience myself but I have learned with dd to separate from her a bit emotionally. Stuff will happen to her that will hurt her. But I have to learn that I am not the same as her, and what happens to her does not happen to me. By separating from her appropriately I can better support her with the tough times.
My elder sis is wonderfully wise about this. She always says they need to get hurt so they can learn about getting hurt. They need to be rejected so they can learn about being rejected. The pain they feel is part of developing them as rounded human beings, it is part of the what will make them strong and happy. It's a vaccination against resisting reality.
My sis has finally go through to me and I am suffering much less. Our children need to feel these tough things and then grow and learn from them (when they're old enough of course)
I just say to DD now, oh we can't go to that party (without too much elaboration) at that age they can usually be distracted.
look after yourself first, you need to separate a bit if you can. For your and their sakes.