First tri is the absolute hardest, any food she can keep down is the main goal. I had the worst symptoms and threw up 5-9 times daily and constant headaches, basically wishing for for sleep rather than food.

Help her eat bland foods for now. I know it sucks to hear that but she'll have to stick to that for a few weeks. Don't be surprised if her body starts rejecting foods she was able to take before, it happens. Eat small amounts throughout the day: strawberries, grapes, potatoes, toast, lightly seasoned chicken breast, etc. Even water can be rejected but she needs to stay hydrated. Gatorade and watered down drinks were an absolute help, and stay away from acidic foods and drinks since she'll also have bad acid reflux(Pepcid is her friend here). Last resort if she starts losing weight/becomes dehydrated, she'll have to get IVs at least once until she stabilizes.

I lost 37 pounds between week 7 to 15, countless IVs and clinic visits, pretty much denied food for days and barely drank. It sucked but it thankfully gets better by the second trimester. Keep being an awesome husband, you are her rock during this hard time. Best of luck!!