I can relate to most of what you're feeling, Switchy. I grew up in a Christian environment, one aspect of it that involved 12 years of pretty interesting private school.
I learned quite a bit about 'faith' during those years. And while, at one time, I could count myself as part of that faith, I don't now. I won't go into why, as that's not something that's terribly important.
What is important is your concern over what's real. I think most of us are familiar with that pondering. It's purely natural, as well... for we are human beings, the great thinkers of this world. To not challenge systems, at least logically, would be against our nature... and perhaps, on some level, the pull of that challenge is what makes "faith" so hard. What makes it such an important aspect of "god". Faith can be defined as "firm belief in something for which there is no proof". When it comes to god, that definition is very applicable. However, many men of the "faith" will tell you that proof of god is all around us. That we are proof of god. For a long time, I believed that without a doubt.
But the human nature of us all made me question that. To the point of being frightened about which path to take. Because if you pick the wrong one... aren't you "screwed"? That's what I was told growing up. The 'narrow path' is hard to follow. They're right. For whatever reason, doesn't matter, they're right.
I could ramble on and on about the dual-sidedness of the issue of faith. About how I see the "Biblical Passages" as a rough guide to life. Old fashioned, albeit, but. I'm a very objective person, which can make it hard to blindly follow either path.
Which one should you follow is up to you, Switchy. I understand your fear, your worry.. "What if I die and see god? And all this time I could have just had faith...", "What if I die and there is no god? There is no continuation of the spirit?". It makes you feel like no matter what you choose, you could be making the wrong decision.
I guess that's where soul-searching comes in. Even after having seen both sides of the fence, and bad and good examples of each, I can only tell you that you're going to have to deliberate this with yourself. Inform yourself, read!, expose yourself to the ways of the world, talk to others you trust and care about.(which you've done here, too! Keep it up hehe)
When you can say that you're "happy" about your feelings on the issue, and when you can say that you truly feel "at peace" with the way you live your life... I think it doesn't matter what happens when you die. Preparing for a future that may not exist is one thing, living your life and being personally glad about how you lived your life is another.