I'm not so sure, from the testimonies of the deconverted. As I noted recently: this Reddit article notes that there is considerable pain in giving up theism, and says that a lot of this pain is realising there is no afterlife. So even if theists lack much of a theory on what happens to you when you die, at least some seem to think something does - it's not just a thought-stopper.
there is considerable pain in giving up theism
It varies a lot from person to person. Some people find it a joyful liberation. Some people find it depressing and painful. Some people find it emotionally neutral and get on with their lives.
(I deconverted from Christianity at age ~36. It was a long and careful process -- I don't make big probably-irreversible changes in a hurry -- but not, in my case, at all painful or upsetting.)
Today's post, Third Alternatives for Afterlife-ism was originally published on May 8, 2007. A summary (from the LW wiki):
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