The question basically implies that we come to a revelation that our belief system is false and therefore, what would you do given your belief system is false? The answer, as with everyone, is that they'd adopt a new one by default. Once you stop believing something, you no longer subscribe to that belief system. Example, a theist who comes to the belief that there is no god, then becomes an a-theist. From that point the atheist can move on to buddhism or whatever else religion.
So, what would I do? I'm sorry, but I don't wish to entertain hypothetical scenarios, especially one that denies the Gospel.