WWF, I truly understand where you're coming from, but I also have to take care that I don't let Satan persuade me to sin in my frustration with them, and sometimes even anger that I can't make them understand.  And Satan will do that, if we aren't careful.  I'm still learning, too, and even God's Word tells us that there comes a time when, just like God will, we have to leave them to their own devices; and I'm just about to that point.  We can pray for them, that the Lord will show them the error of their ways before their time to die, but that's the only thing left that we can do with some of them.