Yes, I know what you mean- it frightens me too. If the designer of the afterlife is the same as the one who designed this world, I don't hold out much hope on it being either nice or fair. I was brought up with ideas of heaven and hell, so it's hard to banish those worries all together.
Still, I like to think the logical part of my brain, plus some of the most intelligent people I have come across have heavily persuaded me that religion and God are manmade concepts.
As a concept, it's kind of weird. If we only have one life and then an eternity in an afterlife- seems kind of bizarre to judge your future in eternity on such a (relatively) small period of time. Plus- we all have varying degrees of shit to deal with... So- some of us may be less likely to 'sin' in the first place.
I guess I just don't get it- even if we are fortunate enough to get into heaven- what are we supposed to do there?!! Life and it's struggles may well be a series of lessons but to what possible end? Sometimes I think 'choice' is our greatest gift- there is no freedom without choice. But where is 'choice' in religion? It seems more like- do this or be punished. What if you don't want the 'reward' of heaven? Do you suppose you can refuse?!! What kind of paradise is it if you're not given choice?
Funnily enough, I just googled the question: 'Can you refuse admittance into heaven?' The results were kind of interesting- some people saying that the only ones who will be admitted will be those who dedicated their lives to the cause and who religiously followed their God's teachings or perhaps unresevedly asked for repentance if they strayed off course. Kind of makes me think I'm going to hell regardless of whether I CTB or not. I'm sure I've sinned plenty and I don't believe in God or its rules enough to feel repentant for all of it.
If it's reincarnation that happens, then all these struggles could well be to teach us some important lessons. But again- to what end? Plus, if the process is supposed to be positive- then why don't the majority of us remember our past lives and past mistakes? It can't be an accumulation of knowledge if we just forget everything each time we are born.
I hope that logic will win out for me in the end. Religion's make a great deal of sense from a subjugation perspective. Where there were/ are huge masses of people who could well descend into chaos- theiving/ murdering/ commiting adultery all over the place, religion hand in hand with state laws asserts order by promising us punishment if we 'sin' and reward if we follow all the rules.