I'm a 20-year-old guy, and my girlfriend, who is 24, mentioned something today that surprised me. She expressed a wish that my father would die—though that’s not exactly how she said it. How should I respond to that?

Today, I was on the phone with my girlfriend (we're in a long-distance relationship), and she asked me if my father is racist. I told her that, unfortunately, he is, but he’s not a bad person; he’s always kind to everyone, even to those who aren't of the same race. While he hasn't made any overtly racist comments or treated anyone poorly because of their background, he does hold some prejudiced beliefs. Then she asked me how old my father is, and after I told her, she said, "So he's going to be around for a lot longer?" She laughed afterward, but her tone sounded serious. At first, I was confused, but then I realized the implication of what she said. I didn’t confront her about it in the moment because I’m worried about losing her, but it still hurt me. I love her deeply, and I know she loves me too, but I’m unsure how to handle this situation.