We are instructed to "Plant the Seeds of Truth" (
Mathew 13:3-9 KJV) in those who we meet in our daily travels. Our responsibility ends there. GOD is the only one who can allow those seeds to take root and we are also told in scripture 'not to cast pearls before swine' (
Mathew 7:6 KJV). In other words, once God's Truth is made available to a potential convert, and they dismiss The Word - don't continue to try to enlighten them. Your time is better spent on those who do have potential to know and love God and His Son, Jesus Christ. God gave us all Free Will and it is our decision whether we will follow God's teachings or those of Satan. God will not force us to love Him.
The spirit of Satan lives inside more and more persons in these end times. This was prophesyed long ago in the Book of Revelation and is coming to pass. The 'eyes' are a window into the soul and in those who have accepted the 'easy way out' and have adopted the doctrines of Satan, their daily demeanor is shown to all by their expressions, deeds and words.
The person that you have mentioned may be beyond what The Seeds of Truth can overcome. It is now up to God to try to make The Truth sink in. If you are uncomfortablle with the situation, distance yourself from that person because you have done all that you can.