Hi there, I’m a 40-something emetophobe who has had it since I was late primary school age. No idea why it came on, but I’ve been dealing with it for around 30 years.
In the beginning I used to sleep sitting up with a bucket in my room (I was never ill). It took about 2 years to take the bucket out of my room. It took a few more years to lie down to sleep. I can’t really remember discussing it lots with my parents but they just accepted my foibles (my term) and if it reassured me, we did it.
I can’t comment on what’s best to get her to eat, but as others have said, safe foods are your friend. For me this is low-risk, carby foods such as potatoes eg jacket potatoes, chips, cereal, toast, and tell her it’s not possible to be ill through these foods. One things emetophobes like is certainty ie control. If she can see they’re ripe / not mouldy, you can tell her there is no way they will be the cause of food poisoning. Let her prepare them with you.
When out and about, it’s important to us to know exactly where the toilet is, especially when on public transport like trains, and in restaurants. Sit somewhere where the toilet is in view. Sometimes we can be irrational, like not wanting to sit in the back of a 3-door car because there’s no access to opening a window or door - that still gets me sometimes on long car journeys.
It sounds really hard OP, but give lots of encouragement and try and give that certainty about foods. Stay away from higher risk foods for now, and in time she will come back to them.
Over time I have got better with age. As I’ve got older, I’ve realised the constantly feeling sick was actually the anxiety of thinking about it making me feel hot and sweaty and nervous. Now I can recognise these anxious moments and dismiss any worries about whether it’s gonna happen.
But it doesn’t go away forever, in a lot of cases. I have intrusive worrying thoughts about it maybe once a day. I decided to have a baby despite my deep concern for morning sickness, but I got through it (using a lot of my usual coping techniques). Now I have paranoia over my daughter being ill but ultimately I just get on with it, because there’s no other choice. I’m proud of how far I’ve come, and your daughter will get better, I promise.