Praise be to Allaah.
Their words are false and a rejection of the truth. Allaah is dislikes such a response. The evidence for that is what it says in the saheeh hadeeth narrated from the Messenger (peace and blessings of Allaah be upon him): “The most beloved of speech to Allaah is when a person says: ‘Subhaanaka Allaahumma wa bi hamdika, wa tabaaraka ismuka wa ta’aala jadduka, wa laa ilaaha ghayruka (Glory and praise be to You, O Allaah, blessed be Your name and exalted be Your majesty, and there is no god but You).’ The most hated of speech to Allaah is when one man says to another, ‘Fear Allaah,’ and the other says, ‘Mind your own business!’”
(al-Silsilah al-Saheehah by al-Albaani, no. 2598)
You have to persist in da’wah, and bear patiently the things you suffer, as Luqmaan said to his son:
“O my son! Aqim-is-Salaah (perform As-Salaah), enjoin (on people) Al-Ma‘roof (Islamic Monotheism and all that is good), and forbid (people) from Al-Munkar (i.e. disbelief in the Oneness of Allaah, polytheism of all kinds and all that is evil and bad), and bear with patience whatever befalls you. Verily, these are some of the important commandments (ordered by Allaah with no exemption)”
[Luqmaan 31:17 – interpretation of the meaning]