Because it doesn’t matter who you’re dating, married to or friends with. Take Thomas Jefferson, for instance. He kept slaves. Human beings that were his property. He also took a liking to one of them, a young girl called Sally Hemings. When Jefferson’s wife died, she became his de-facto partner, concubine, and the mother of several of his children. Children who, like their mother, were legally the propery of their father.
Now was Jefferson always evil and vile to his common-law wife, who was also his slave? Not necessarily. In fact she enjoyed certain privileges. Some of the children he had by her, he treated well. He saw it to they enjoyed a better education than the other slaves at his plantation.
So you can be racist as hell, literally keep slaves, and still have a bit of a ‘soft spot’ for one or a few of them. Of course to us, today, the very concept of owning your own family, literally owning them as property, is sick. Even in his day, some were weirded out by it. Jefferson didn’t claim the kids as his own. But he did set one of them free, later in life.
By today’s standards, Thomas Jefferson was a disgusting, horrible racist. Not to mention the fact that Sally Hemings was just fourteen when he began bedding her. For his era, though, it should be said that he was relatively benign, maybe even considerate, as far as slave owners go. Still hella racist though.
People are complex. Racists are people, so they, too, are complex. Derek Chauvin may been awfully sweet to his now ex-wife. And decidedly not sweet to the defenseless, unarmed and tied up man he murdered in broad daylight.