The Bible is clear on the subject of suffering. It makes no statements about God's desire for man to live in a perpetual state of happiness. The book of Ecclesiastes is littered with frustration about bad people not getting what they deserve. The book of Job is the story of a man who God allowed deep suffering and torment to satisfy what appears to be a game with Satan. These subjects are controversial and strange from a human perspective...but God is not a human.
If one were to hold to the suffering as proof against the existence of God, they inadvertently choose illogical reasoning to do so. Here is an example: All people have parents who apply rules out of concern for the safety and moral character of their children. If one were to say to their parent, “If you do not let me stay up past my bedtime, you do not exist,” they are making an irrational statement. The same reasoning applies to people's perception of God. To establish whether God exists has nothing to do with what He does and what He does not do. If God exists, then He simply exists. However, this still does not establish any moral satisfaction as to why people suffer.
Sometimes, a simple understanding that God's ways are not mankind's ways is not enough to bring the problem of suffering into perspective. Job suffered many heartbreaks, he lost everything except his wife who encouraged him to “curse God and die.” In the end, Job did the opposite. He did question God as to why He would allow these things to befall him, but never did he deny the goodness of God.
The question is not will Christians suffer, it is how well they suffer. The choice lies within each of one's heart to use misfortune and circumstance for justification of either poor behavior or honorable suffering. There are options one must weigh to explain the problem of pain. To simply say God does not exist will never satisfy the problem or rid the world of suffering, nor does it prove He is non-existent. The truth that God does exist at least offers the hope of understanding the dilemma of suffering.