faith

IDK if others tell you this directly, out of politeness for a religious affiliation, but generally when we interpret things as "signs" (other than those intentionally designed by people) that is called Magical Thinking, AKA superstitious thinking. By superstition I mean a belief that events are causally connected despite the absence of a plausible causal link between them, especially as a result of supernatural effects. Could be an assumed link between objectively real things, like stepping on a crack and then an actual house fire. Or can include imagined events, like a dream and communication from an invisible telepathic entity. There's a lot of insightful info to search for about this most common cognative distortion. It's very reinforced by cultures, and even screws with people who don't struggle with an obsessive anxiety disorder like us. I think it's a lot easier for a therapist to tell us our magical belief is just in our head if it's not associated with any religion. Like if every time someone spots roadkill they interpret it as just a sign from "the universe" that their pet is about to die, so they always rush home in a panic and won't leave their pet for days, just in case. So a therapist could more comfortably point out how that's simply irrational. But if they say it's actually an omen related to some religion, then the therapist has to be very careful to tip toe around invalidating their highly valued belief system. Some will meet you where you're at by granting the premise of the beliefs but try manipulating them in some less scary direction. Like "well, what if the roadkill is actually god just leaving you a reminder to be grateful for your pet being alive and well?" Or the therapist might actually share the same religious belief themself, if it's a popular one. Just food for thought. And whatever you believe in, I hope you will treat your body however you reasonably think is healthy for you. Consider that there will never be any shortage of conflicting signs (imagined or intended marketing) telling us to follow all different diets or other life choices. You must be empowered to be the decider of what will serve your best values.

Let this be your sign to not be obedient to ODC! BTW, I wonder what kind of things you'd interpret as a sign? In case it's something you'd like sharing. This also has me thinking, even IF I see something I'm convinced someone intentionally made as a sign telling me to think or do something, like to marry someone or to starve myself, I don't think I should just obey it without agreeing it's a good idea. If I see an official sign posted on the edge of the Grand Canyon that reads "JUMP HERE" I don't think I'll feel bad about passing on that command. I guess the difference is if we are told who the respected sign maker is, and have been taught to always trust his signs more than our own sense of things. Then maybe that could override my own best judgment. Or he'd just loose my trust in unreliable signs.

No, you cannot be unsaved like that. The Bible says nothing about that so you’re good!

Fasting can be a compulsion, it was for me until I made myself sick. Please do not fast if you have OCD. God does not wish you to be sick

Remember suffering for sufferings sake is not what God wants. You already suffering with OCD, you do not need to add fasting to that. That is not what pleases him.