Why not be a Buddhist or believe in some other religion then? They also offer something that will make you feel comfortable with your belief; Christianity is nothing special or unique regard to some existence beyond your current life.
"I couldn't imagine going through life believing that this is all there is."
I couldn't disagree more. This precious life, even with it's ups and downs, is awesome!! And, as far as we know for certain - as it's happening right now - it's all we have. The fascination with a possible after- or next-life is a dangerous one that twists many people's actions and motivations.