I’m afraid that there may be no afterlife. That’s the long and short of it.
Look at me posting in offtopic.
So, here’s where I think a reframing of the issue could help. Take the lack of your traditional metaphysical afterlife, consciousness of any sort after death – just take that as a given, not a mere possibility (big help so far, I know, just hold on a sec while I get there)
If “what’s past my death” is as important to you as it seems to be, then try to focus on what does without any question outlast your body. Your works, your friends, relations, younger people you have influenced, everyone who will have a memory of you. How will you be remembered? Not in an egotistical sense like “Shit you mean I have to discover a cure for cancer or nobody will remember me in 500 years?!” More like “When I’m gone, I’ll have left my corner of the world a slightly better place. My passing will be marked, and I’ll be missed” sense. If you’re not sure this is true, that’s the good news–you’re still alive. You can do this. Even if you’ve made some phenomenal mistakes and you fear your net effect on the world is negative, you have time to turn that around (even if it means not changing what you do, so much as thinking about what you have done less negatively).
And, back to the first point, let’s say the metaphysical afterlife turns out to be real. If you’re already at peace with yourself in the sense described above, I don’t think that could do anything but help.
Full disclosure: I’m atheist, but not of the Dawkins ilk. I totally see the appeal and helpfulness of many religions in dealing with this and many other difficult issues. I don’t intend to dissuade you from faith if that’s the path you decide to follow.