i would assume these are intrusive thoughts considering your distress and lack of attraction. these are totally normal to experience, it doesn't mean that you secretly have incestuous desires, it's actually the opposite. it's your brain trying to double check that you are still uncomfortable with ideas that go against your morals. even if you did find yourself attracted to your family, my advice would be the same; as long as you have no intentions to harm them in real life, you are totally fine. there's no such thing as a thought crime, it's your actions that matter. don't feel ashamed for something you can't control, especially considering what you are experiencing is associated with sexual OCD.