Relating to God No Longer

Many people speak of family members or friends who no longer go to church or pray or seek God. Some call this "back-sliding". And no matter what they do, or how consistently they present a message that God is still relevant, this all seems to fall on deaf ears. I have an untested theory, that such people need a new faith entirely - attempts to rekindle something that now hardly exists will NOT work. Can you help me with my thinking and research on this? Two reasons why trying to rekindle the past will NOT work in my opinion: (i) there are bad experiences unalterably attached to faith of the past; (ii) the faith of the past, if it does not exist in reality today, was likely borrowed (from say a parent) and was more about people-pleasing, than it was real. So why won't the "back-sliders" (a term I'm not really comfortable with) return? Because there is nothing substantial to return to, or, what they might return to is so tarnished in hypocrisy, abuse or neglect, nothing could be further from their mind. Please contact me at warrenhodge@optusnet.com.au if you have any insight on these matters. Thanks.