I feel the exact same way. I consider myself Agnostic, I have a lot of confusion regarding personal faith and beliefs. I could rant and go on and on about this however my point is, that once in a while I get absolutely white-knuckle terrified when I think about death, in my mind, when I die - there will be nothing. Ever. I would love nothing more than to believe otherwise but I can't compute the possibility of faith (for me). I just can't.
I'm mentioning this to you, now, because how I deal with it, is I sit back and think about my life as it's been so far (I'm only 19) and I think how well I've done in terms of education, how lucky I am in terms of living in a 1st world country, various different memories, my family, my girlfriend and how much I love her, and more recently my kitten (Revan). These things make me smile the most, and are what make my life worth living and at the very least, serve a proper distraction.
What I suggest, is perhaps sit back like I do and just think and remember all the good things in your life, and if a smile sneaks its way through your terrified exterior, then it's not so bad after all.