I am allergic to some esential oils used to make perfumes and colognes. Reactions range from slight discomfort (sneezing, runny nose, sinus pressure, headache) to all out anaphylaxis. Do I expect any airline to pre-screen every passenger who boards a flight I'm on as to what kind of perfume, cologne or body spray they've used? Absolutely not.
With a nut allergy, even if the airline were to remove all nut products from the flight (and you should pay attention to labeling on food products as they may not contain nuts but were processed in a factory which also processes nut products) it does not preclude that another passenger will bring on a nut product as a snack in their carryon. I'm sorry but I have to agree thast an allergy is a personal problem. You can't expect any establishment from a restaurant to an airline to provide a completely allergen free environment.
My advice is to move into a bubble-house and buy a Learjet if you need to fly.
Rant over.