History

My grandpa died this year. I wasn't angry that he left; he had been defeating cancer for the past five years and he was nearly ninety. He was the kind of man you could count on. Anytime his family needed a new shelf built, a basketball hoop, someone to pick the kids up from school, he was there. He treated us to ice cream cones, and more than once bailed my parents out financially. He took care of the ladies down the street and planted flowers for his neighbors who were too old to do it for themselves. He was selfless and kind and in love with my grandma until the day he died. I was angry, not because he had cancer, but because the God that I had committed my life to said in his word that my grandpa deserved eternal torment in hell. This was the first time that I was faced with the uncertainty of a loved one's eternal life. My grandpa died with love for his family and friends, but none of us were really sure about his faith. He had been a semi-regular church go-er, but had some difficult experiences with religion in the past that kept him from really trusting it again. The moment that he died, my security in the character of God began to crack. What made my grandpa so different than me that God would allow me eternal life, but not extend the same mercy to my grandpa? In scripture, He makes it very clear that none of us deserve his love and mercy, so why do only some of us recieve it?
Everyone who calls themselves a Christian has certain areas that sit unsettled, sticking points about their faith they hope no unbeliever asks them to explain. For some, it's predestination, for others, its the stories of God's ruthlessness in the Old Testament. I always had a list of questions/problems that didn't sit well with me, but the pros of my beliefs always seemed to outweigh the cons, and because I was so sure that God was real and most importantly that God was good, I allowed myself not to think of these difficulties.
With this deep crack in my faith, allowing me to ask questions I never had before I began to examine all the basic assumptions of my faith. How do I know God? How do I know the Bible is accurate? Is there even a God?
Each post hereafter will be some piece of an answer to these questions. I want to know if there is a god and the ramifications of that answer. If yes, how do know anything about him? If no, what does that mean for the purpose and meaning of my life?