That's interesting, yes it makes sense that something like that would take some time to process.
You don't need to be into religion to undergo some kind of change like that. I don't know this person but acting really puts you in contact emotions and memories, not to mention it surrounds you with a more artistically, open minded crowd which can really influence you, in this case for the better. But maybe the trigger was something else entirely...
Sorry about the anxiety, that's rough. I've also hated people for years, it's a burden. Hope things improve for you