Turn the other cheek, don't be angry with your brother, etc.
"Turning the other cheek" refers to bearing personal insults. This CE nonsense isn't an attack on me. It's an attempt to diminish the greatest event in history, the birth of Christ. Christians are obligated to defend Christ.
Righteous anger in the defense of Christ, or directed against evil, is no vice. Remember that Christ drove the moneychangers out of the temple with a bullwhip.
With regard to my original statement, How exactly can a person physically stick "CE" (words denoting an idea) where the sun don't shine? It's a figurative statement, and in that sense, it's an appropriate statement, since the motivation of those promoting this idea is evil, if not demonic, since people of other religions can use their own calendar. There's no need to bastardize the Christian one.