Racist "friend"

I keep my circle small to try to avoid garbage people. However recently a girl who I held in high regards said somethings and well it kinda made me see the crappy side of her. * backstory : We are having to undergo ivf and we chose to use a different race donor. * She was having a conversation with a coworker and the comment was made : "We dont mix races, its not what god intended. If so hed have made us a zeba." Our coworker glanced over at me, back at her and shook her head. As soon as she realized I had heard her, she said " I dont judge people who do." Apparently you do. You cant be partially racist. Its really been bothering me. Any ideas on how to handle it?