How can I get people to fully understand the seriousness of my life threatening latex allergy?

Educate. How about downloading information from the american latex allergy association (latexallergyresources.Org) and share it with your friends?
Latex allergy. Provide information to people by using the aaaai & acaai website for resources. And ask your allergist to write a letter on your behalf. Also, wear a medic alert bracelet and always carry two epi pens.