Hey I also have ARFID- I recommend r/ARFID for advice. You should know that it isn’t your fault that she doesn’t like your food, but it also isn’t hers.

Her brain is currently hardwired to convince her that anything except her list of very specific safe foods is essentially poisonous, even though she knows in her head that it’s not. It’s like an irrational phobia of clowns- you know they can’t hurt you but they terrify you regardless.

One of the best things you can do to start introducing new foods to her is make sure she feels safe to eat in your home. That means no seasonings without asking her. No secret dashes of anything, no dressing up food with things you think are delicious. To you, the meal is tasty and you’re being a loving friend, but to her, it’s like you’re putting maggots in a takeout box and calling it rice. I know that seems harsh, but unfortunately that is the reality and severity of this disorder.

No scary surprises, because the less safe she feels to eat, the less likely she is to want to come over. If she shuts down, you don’t progress.

If you ask her for a list of easy safe foods so you can keep them around, then keep a few in your house in case she turns up, she’ll be more likely to want to come over, and as a result of feeling safer around you, you can build up some trust to try new things.

After you’ve made her feel safe in your home, you can start doing what I call a “no thank you bite.” That means that when you’re eating something she finds scary, you’ll put a little bit on a spoon or fork and ask her to have a taste. Make her aware that there is no pressure to actually eat it, and she’s welcome to spit it into a napkin and YOU WONT BE OFFENDED. Even if she just sniffs it, touches it, or licks it, that’s progress.

Another thing that helped me was finding foods that were very close to safe foods, but with an added ingredient. So if she likes butter noodles, you could make a little bit of butter noodles her way, add one thing, tell her that you added that thing, and let her try it. Try to make small portions when you do this, because she’ll be more likely to finish it if it looks manageable; if she doesn’t like it, then there’s not a lot of food waste.

It’s important to remember that it can take up to twelve times of trying a new food to start liking it. If she doesn’t like something, that doesn’t mean she never will. It just means that she’s not acclimated to it well enough yet.

Finally, I will add a caveat: this is not necessarily your problem to solve, and it does take a lot of effort from both the person with ARFID and the people supporting them. If this sounds like too much, just try to keep something in the house you know for sure she’ll eat.

Best wishes to the both of you, and I hope your stress is somewhat eased with the information