Jack and Jill went up the hill, to cheat on each other. Jack fell down and ended his affair, but Jill has yet to come tumbling after. (Sorry, couldn't resist.)

Re LW1: Please ease up. There are not many ways in which people really change, but this is one of them. I am in an interracial marriage, and a few people that we had to keep at arm's length at first are now vocal anti-racists and some of my favorite people. We know that racism comes from ignorance and isolation. With most people who are basically kind and at least somewhat intelligent (like the people who raised your wonderful girlfriend, no doubt), it usually doesn't take too many contacts with people who don't fit the stereotypes to stand people's assumptions on end. You should never put up with hateful, hurtful comments, and you should leave, without any fanfare, any situation where this happens. Otherwise, just be the best person you can be, and they'll gradually realize how ridiculous they are in comparison, if they haven't already.

As regards to Denise and BB, I have a simple suggestion, I think.
The home was a new anchor, and indication of commitment on your combined part - to each other. The "in-laws" don't have to preside in the driver's seat in this dynamic. Have a homewarming party - at your place! Send out your own invitations! You're on your own turf, and you can be exceedingly, exquisitely attentive to those that have slighted you. Kill them with kindness. It's a litmus test for those that don't respond, but I would bet my bottom dollar that most will *adjust* their personal prejudices immediately.
Then, take the high road and accept that new person into your life with whatever caveats may be necessary.