It is quite painless to become an atheist. It may take some intellection over time but I have found there are no deleterious effects or withdrawal symptoms connected to loss of faith. It is like losing nothing, a vacuum, so insignificant and nebulous is the very nature of faith which indeed is little more than a foundationless assertion of belief. When it is gone it is not missed. It is little more than a bad habbit let go of.
There is a process of disintegration as one lets go the airy premises of faith but the re integration that follows it,the adjustment to a pro reason outlook follows a logical progression that is as painless as it is rewarding.Like removing blinkers the consequences of abandoning faith are salutary and the only regret is that one has wasted so much time believing something so ridiculous and absurd, realising one has been the victim of a scam or a hoax and feeling a little silly.
It can take a while however to fully divest oneself of the vestiges of faith for it is insidious and like an abandoned habbit it can make appeals upon one to backslide and capitulate to it on a subtle level that must be guarded against but such appeals can be quickly dismissed by the application of reason against which it has no defense or power and is consequently thereby vanquished.