Apologist Matt Slick's atheist daughter tells of her experience growing up

[Doubting Thomas]

Atheists frequently wonder how an otherwise rational Christian can live and die without seeing the light of science, and I believe the answer to this is usually environment. If every friend, authority figure, and informational source in your life constantly repeat the same ideas, it is difficult not to believe they’re onto something. My world was built of “reasonable” Christians — the ones who thought, who questioned, who knew that what they believed was true. In the face of this strength, my own doubts seemed petty.

Typical communal reinforcement which is all too common among religions. Most Christians I know tend to do this, surround themselves with like-minded people so that your beliefs are constantly reinforced by others agreeing with them.

Basically it's the same thing as Republicans watching Fox News or listening to Rush or Hannity.