The deepest truths in life are lived, not Boolean affirmative or negative. People will go to extreme measures to keep these truths intact. This is why people (including Christians) largely control their beliefs by who they let into their lives. A truth as deep as whether or not God is involved in one’s life is either experienced or not experienced. The best way to stay Christian is to keep your distance from the people for whom this incarnated truth is a falsehood. This is why youth directors’ worst album is Nine Inch Nails’s Pretty Hate Machine. Because that is about a man seeking God and truth and finding nothing.
Modern Christianity largely transpires on the seat of the emotion, not the intellect. This is especially true in denominations that promote praise and worship music. The problem with this is for some people (particularly those who are emotionally stunted due to mental illness or other pathology) it’s more difficult to feel God is real even than to know he is. The experience of worship really only keeps working if one has the emotional bandwidth to keep feeding them self stories of God saving and sustaining them over and over again. This is also why Christians are so concerned with one’s “heart” being right and one not being bitter. Because there is so much of an emotional component to the whole thing and once something goes awry with the emotions the faith will often follow suit.
A lot of prayer runs up against zero sum situations. God answering your prayer for that job necessitates that another person vying for that job has theirs go unanswered. So much of modern life revolves around competing for a limited amount of resources so praying is akin to asking divine blessing to outbid someone else for scarce resources (like a house in a good neighborhood, a good job, a man with a good job, entry into a selective school, etc..). It’s like a Mario Kart power up. That star will get you ahead but that necessitates others falling behind.
Experiences of God are heavily mediated by the brain. This is why there are millennia year old institutions that tell us who God is and none of them seem to agree. Scientific truth on the other hand is easy for scientists to agree on. It is also why science based treatments for mental illness work so much better than religious ones. Once the brain goes, so does God.