A restless evening

So, here I am trying desperately to sleep. I know my body needs it. I went to a costume party last night and I've been trying to recover from the stomach spasms that decided to hit me at about 2 am. There's something seriously screwed up with my stomach. It really doesn't like me some days. Maybe it really is a gluten problem, I don't know. Anyways, long story short, I've been in pain since 2 am and it finally stopped around 7 pm tonight. I watched a few shows with my kids and now they're asleep.
My brain will not rest. I believe I'm a bit neurotic. I don't know why it is that God decided to make us aware of our own impending death. To be aware of your own mortality is a mental torture that I cannot get away from. I hate it. It makes me crazy at night. I don't know why I cannot stop thinking about it.
I hate knowing that I'm 29 and that if I'm lucky, I'll live until I'm 80. I hate having a life expectancy. I have very little faith in an afterlife, no matter how much I believe in God. I always have this nagging sense that it's a trick, this whole religion thing. Like it's a cop-out so we don't have to be so freaked out about dying.
I don't know. My oldest son is aware of dying and he asks me about it and it scares him (understandably so). I had hoped that by this time in my life I would be able to reassure him and really mean it. Now I tell him that there is a heaven and I don't even fully believe it myself. I truly wish there was a heaven and I want to go there. But I have such a hard time believing it. I'm so scared of dying. I don't want to lose my consiousness.
I think I must be crazy. Why can't I just be like everyone else and not think about it or worry about it? I can convince myself of that for a few days sometimes but then I just get right back into that weird thinking. I guess it might be easier if there was someone to turn to at night and just hold. I feel so alone and all these spinning thoughts of my own mortality don't go anywhere. I know the idea of "You can't control it so why worry about it" should work. It just doesn't for me. I just have to pretend it's not going to happen somehow.
I hope I can get closer to God soon. This is making me insane.