This year, I have dealt with a number of more uncomfortable allergy situations, mostly due to people forgetting. If you are not around an Allergic Reactor all of the time, it is much easier to not remember both how severe their allergy can be, and how to be careful so they don't feel uncomfortable.
Last month I went to a newly discovered bookstore in my city. I met one of my Italian friends there to have a coffee and browse around the store. When we ordered our drinks and sat down at a table in the cafe of the bookstore (which is very uncommon in Italy to find), chips and a variety of nuts were brought to the table to go along with our drinks (this is something that is typical here and doesn't surprise me anymore). My friend started snacking on the nuts, and although they were on her side of the table, it did still make me feel a bit uncomfortable. I felt like I had to be more on-guard about her movements and what she touched. She knows about my allergies, but I did need to remind her about the severity and that I couldn't touch them, etc.
This experience reminded me that sometimes even people that know about my allergies can still forget the severity, and that sometimes people that I infrequently spend time with, may need a brief reminder! Don't be scared to remind people! It is important as an Allergic Reactor to keep yourself safe!