Unclean Spirits

"Unclean spirits" were very present in the gospels. We hear of Jesus expelling or "exorcising" them, usually in a dramatic fashion. In today's Gospel (Mark 3:7-12) we are told that Jesus "warned them sternly not to make him known". Many people are puzzled over this, since it would  seem that having Jesus know would be a good thing. Ah, but then we remember that He was speaking to beings who did not want people to listen to His teaching or follow His example. This makes all te difference.
How many times have you heard unbelievers speak about what we believe? And they are almost always exaggerations, misstatements or outright lies. You see, that is what happens when we allow someone else to define us. The same is true of the Lord. His detractors tried to portray Him as a troublemaker, threat to Rome, threat to Judaism. And, ultimately, this is what led to His death. But even that, we see, was able to be turned around into a blessing, because Jesus did the will of the Father by accepting His death.
In our own lives we sometimes allow others to define us, our beliefs, our religion, our Church, our God in ways that are not true. And, sadly, we often sit back and take it, afraid to cause trouble. I sometimes read other blogs and comments on different articles and am amazed at the amount of disinformation that is out there, especially about people of faith. What are we to do?
I, for one, usually sit back and take it, not wanting to engage others in what I am sure will become a nasty attack on me and my beliefs. Of course, being a priest I am often a prime target for receiving people's anger about  past real or perceived hurts by "the Church". Naturally I accept this as part of my role in the Church, but I need to reconsider my reaction and see if I should be a little stronger in speaking out against these falsehoods.
I wonder how other Catholics, Christians, believers deal with similar situations? When people start bad-mouthing God, religion, the Church, what is the reaction of those who claim to be part of the Body of Christ? Do you allow others to define your beliefs or do you challenge them and declare "that is NOT what I/Catholics/Christians believe!"? The harm done by the "unclean spirits" in the gospels is clear. Perhaps their greatest success is that today we do not consider that these unclean spirits are still in our midst, and still spreading false notions about Jesus. What do you think?