While there are some people that don't believe in God, their non-belief does not and cannot change the fact that God is our Creator. Then there are plenty of others that believe in God, but their conception of God is flawed and thereby isn't correct, for the attribute the wrong characteristics to God, and then the corresponding wrong beliefs. So too, there are others that have the basic conception right about God, though somewhat flawed and flayed at the edges, but their conception and belief are basically in accordance with God and His laws. Finally, there are those that implicitly know God, though not many, these are the true prophets, gurus, and mentors of our present day.
There are many people that pray to God, on a given day, some by rote, some half-heartedly, some at meals, and some with real vim and vigor. Some believe that God only exists within certain edifices, or by adhering to certain words, incantations, procedures, and behaviors. So too, there are a special few that pray continuously to God in the sense that God is foremost in their heart, in which their thinking and actions reflects this ever present connection.
In any event, unlike human interaction, the presence of God in any one individual's life, in which God appears so real as to be a living and breathing entity, of which, we are able to thereby absorb into ourselves his Being so completely that we are enveloped by God, and are thereby able to comprehend what is being spoken to us in non-verbalized words that touch our heart and soul are infrequent to say the least, of which most people never experience on earth this closeness by God.
However, keep in mind, that when we pray, we are implicitly asking for God's presence in our life, so then it shouldn't be completely unexpected if God did actually appear to us. You might think, though, that all that pray for God, would be overjoyed when God came within their presence, but in actuality when you recognize that you will be facing the Creator of the universe, alone, and that God knows absolutely everything about you, good and bad, your self-confidence will undoubtedly wane to a highly alarming degree, for it is one thing to theorize about God, and it is another thing entirely to actually face God, knowing that in so many ways, big and small, that you have in your words and in your actions, failed completely in your life to be loving, truthful, and just.
On the other hand, people that are incapable of self-reflection, or fools, don't fear God and are thereby eager to face God, and will therefore welcome God with open arms, only to find out to their utter dismay that they will feel strongly compelled to suddenly drop to their knees and to place their head, face down, and will shut their mouths as well as silence their tongue, for when faced with the overwhelming power and truth that is God, they are fully exposed for who and what they really are, of being an abject failure, a pretender, and a fraud.
God is truth, love, and justice, and if you are not all three of those things in everything that you do, all of the time, your shame will be immense and your tears will seemingly never end.