OP, here is something I'd like to share with you that I've learned in my experience. Firstly, not everyone who claims to be an atheist is actually an atheist, rather they are really anti-theist. They are against the idea of God, they are against the idea of Christianity, and they are against the idea of religion. But they do not take atheism to its logical conclusion. Here are just a few examples to illustrate what I'm talking about. These are not supposed to be evidences or "proofs" for God or Christianity, they are simply questions that I hope we all ponder, regardless of what we believe.
1. If there is no God, the big questions remain unanswered, so how do we answer the following questions: Why is there something rather than nothing? Why is there conscious, intelligent life on this planet, and is there any meaning to this life? If there is meaning, what kind of meaning and how is it found? Does human history lead anywhere, or is it all in vain since death is merely the end? How do you come to understand good and evil, right and wrong without a transcendent signifier? If these concepts are merely social constructions, or human opinions, whose opinion does one trust in determining what is good or bad, right or wrong?
2. If we reject the existence of God, we are left with a crisis of meaning, so why dont we see more atheists like Jean Paul Sartre, or Friedrich Nietzsche, or Michel Foucault? These three philosophers, who also embraced atheism, recognized that in the absence of God, there was no transcendent meaning beyond ones own self-interests, pleasures, or tastes. The crisis of atheistic meaninglessness is depicted in Sartres book Nausea. Without God, there is a crisis of meaning, and these three thinkers, among others, show us a world of just stuff, thrown out into space and time, going nowhere, meaning nothing.
3. If there is no God, the problems of evil and suffering are in no way solved, so where is the hope of redemption, or meaning for those who suffer? Suffering is just as tragic, if not more so, without God because there is no hope of ultimate justice, or of the suffering being rendered meaningful or transcendent, redemptive or redeemable. It might be true that there is no God to blame now, but neither is there a God to reach out to for strength, transcendent meaning, or comfort. Why would we seek the alleviation of suffering without objective morality grounded in a God of justice?
4. If there is no God, we dont make sense, so how do we explain human longings and desire for the transcendent? How do we even explain human questions for meaning and purpose, or inner thoughts like, why do I feel unfulfilled or empty? Why do we hunger for the spiritual, and how do we explain these longings if nothing can exist beyond the material world?
I have yet to meet an atheist who can give any sort of substantive response to these questions. The "serious" atheists (as I refer to them) such as Sartre and Foucalt, readily admitted that "Yes, if what we say is true, there is no meaning, there is no good, there is no evil, there is nothing, everything is meaningless". Modern day "atheists" don't want to accept that message of doom and gloom - and who can blame them? They want to live a life without God, but they still want to hold onto things such as hope, love, meaning, and goodness that are ONLY possible with God. It's a sad irony.