Since the Virgin Mary is such an important figure in Christianity, it's logical to think that some Christians will hold that blasphemy against Mary is a serious offence, even if not as serious as blasphemy against God.
Please see the Catechism of the Catholic Church, 2142 and 2146:
CCC 2142 The second commandment prescribes respect for the Lord's name. Like the first commandment, it belongs to the virtue of religion
and more particularly it governs our use of speech in sacred matters.
CCC 2146 The second commandment forbids the abuse of God's name, i.e., every improper use of the names of God, Jesus Christ, but also
of the Virgin Mary and all the saints.
With these, one would then easily recognize when the sacred names and those of the saints are improperly used.
It is observed and commented that when people learn a new language, bad words are among the first to be learned. Christianity - Stack Exchange being a question and answer site for committed Christians, experts in Christianity and those interested in learning more, I believe providing examples would not only be inappropriate, but might also be in itself contravening the second commandment.