The answer engenders something similar to how scientists deal with accepted theories/hypotheses. Anytime a problem or an anomaly comes along to challenge the overarching paradigm, the scientist is not to give up the entire paradigm at the hands of questionable doubts. Instead, the person continues to search for answers to the particular problem until there is a resolution. Even still, you must remember that reason is subordinate to faith in that reason serves as the handmaiden to faith. If the evidence just isn't there for God's existence or the truth of Christianity, we have our personal encounter with the living God whereby we know that He is real. If the evidence happens to confirm that faith, then so much the more is our faith enhanced. Now, I do not say this as if I'm backing away from the idea that Christianity doesn't have a case. It most assuredly does. In fact, I believe that if anyone examined the evidence thoroughly (I mean "completely") then I am convinced the evidence would point to the truth that God exists and that Christianity is true. But no one can exhaustively examine all of the information in the universe in order to attain that level of confidence. So, we say that based on the information we do have, there are reasons to accept the Christian worldview. We see this paralleled in other scenarios. Suppose that O.J. Simpson, who is on trial again in Las Vegas, really didn't do what he's accused of. Now suppose that the evidence is mounting heavily against him. In the face of the evidence leaning toward his guilt, is Simpson now obliged to change his mind because of what the evidence says? Not at all. Similarly, the evidence is a tool for the Christian and the skeptic alike. But in this case, the evidence favors the Christian worldview. Getting the skeptic to see this is a bit of a journey through the mire. And last of all, we must remember that spiritual forces in dark places are actively at work against the Christian believer. Satan is not content to sit idly by while anyone pursues a relationship with the Lord - not even Jesus was off this hook (recall His 40-day temptation in the wilderness). Immerse yourself in prayer, fellowship, worship, and the Word of God so that you can stand against the attacks of our enemy.  When a question is brought to our attention that casts doubt on our faith, pursue answering that question into the ground!  Shelve those questions you can't resolve until you gather the right assistance or resources to answer it.  But always hang in there!  Not all questions are resolved easily, up front.  It take a bit of study and alot of patience.