When people are conflicted, there are two voices inside them. If I get involved, I'm picking a voice. Whatever voice I pick, they'll pick the other voice. If I pick the 'right' voice; they'll pick the 'wrong' one. The risk is that this will further deepen their attachment to the wrong one. I'm actually preventing progress. I'm not assisting it.
This is why, when someone is conflicted, the best thing I can do is hide.