Good luck. If you don't get it out tomorrow, you can always wait until your baby has arrived. Once you look down at that little face depending on you...it is much easier to tell the person exactly what you think of their rude/racist/hurtful comment, friendship or not! My DH had a similar problem at work before we brought our DS home. He was the new guy, didn't want to cause too many waves, trying to lay low until he got a feel for the place. But once our DS was home...look out! It was very easy for him to say "I don't appreciate that comment/joke, is that how your really feel?" Now if someone makes an inappropiate joke or slur, they are faced with silence and everyone looking to DH to see what he will say. Many times the person apologizes before he even says anything.
Good luck. I hope your friend sees the error of her ways and finds ways to be more supportive of your journey!