That´s such a shame. I´ve got a friend who also had an allergy like that: totally lacto-intolerant. She has terrible trouble in Venezuela because things like soy and almond milk are hard to get hold of.
I'd be quite happy if it was an intolerance. For me, it is full blown allergic reaction anaphylaxis, to dairy protein. Even in medication, it can trigger an anaphylactic reaction (and has done numerous times.) I need to carry 2 epipens around all of the time and my last incident needed 5 medications in total to control it (2 nebulized medications for breathing related issues, both epipens, an antihistamine tablet & emergency hydrocortisone,).
Sadly the whole incident arose from the simple fact a
cook in a hospital kitchen didn't know the difference between an intolerance to a dairy sugar and an allergic reaction to a dairy protein and despite me saying I needed a vegan diet, thought it fine to serve me lactose free ice-cream labeled as sorbet! (it's actually that last part that I'm furious over. if he had labeled it for what it was, I'd have known I couldn't eat it and returned it as a near miss . instead I could barely breathe, couldn't talk because my throat was so swollen and so on.)
the irony is that when we were traveling, it was actually very easy for me to avoid dairy because in many countries it has not crept into every aspect of our lives and isn't hidden in food to the degree that it is in 'western' society. bread in just bread in most countries. it isn't enriched with milk unless it is a special occasion or religious celebration. and people respect your wishes. if you say no dairy, they will accept it.
sadly in the last incident, it was simply ignorance and a failure to read the container. he didn't understand that removing the dairy sugar from milk meant it was still milk nor did he understand that you can only be intolerant to dairy sugar (lactose) not allergic and I'd specified and written "allergic to dairy protein". I'm not certain how you educate someone to understand the difference between sugar and protein because for me it's a fundamental concept and working in any kitchen, it is something you should know.
I can understand someone working outside of medicine not knowing the difference between an intolerance and an allergy, and understand the general public not knowing that you can't physically be allergic to lactose (the body doesn't possess the ability to be allergic to lactose, only to casein or another dairy protein). but soneone working in catering should know, especially in a hospital kitchen (at least in my books)