Faith.

Faith:
1) belief that is not based on proof: He had faith that the hypothesis would be substantiated by fact.
2) confidence or trust in a person or thing: faith in another's ability.

I have seen a quote before, i can not really remember where. If you know, please tell me so i can give the credit. This quote is NOT mine. "Believing in something unseen is faith, believing something that can be seen is knowledge." This is very true! When you say where is God? I can not see Him. Then where is your faith?! If God were to show Himself to everyone, then it is knowledge and not having faith in God! Then how do we separate those who truly love God and those who do not? So STOP doubting! The Lord our God EXISTS! He is the one and only God! Though we may not see Him, have faith! So stay strong in your faith, because one day, you are going to meet Him in Heaven! God bless you!

2 Corinthians 4:18 So we fix our eyes not on what is seen, but on what is unseen. For what is seen is temporary, but what is unseen is eternal.