Honestly, I think some people either ignore what I'm trying to tell them or pretend not to understand it, because it makes them uncomfortable. I think they understand a lot more than they're letting on. But that's just my opinion.
When this happens, I just stop talking to them. What's the point of trying to communicate at all when someone does that? If they ever decide that they're ready to have a real conversation with me (which I hope someday they do), then we can talk.