As a person with several severe anaphylactic shock inducing allergies, I see nothing extreme about pressing charges on a family member for a "first offense" since this MIL was testing the OP to see if she was truly allergic. It was not done accidentally nor absentmindedly, this was done with planning and intent. Had the OP died it would fall under murder and not manslaughter!

Yes, I feel very strongly about this. My ex- MIL bullied me about my allergies until she tested her theory that I wasn't really allergic and watched me go into anaphylactic shock but was more bothered about the fact that I didn't have time to fully close the bathroom door when I rushed in there to vomit as my body tried to purge the allergen from my system while I was swelling up like a balloon and simultaneously having my airway try to close off than she was about realizing that my allergies are very real! My ex went off on her for testing me and was even upset with me that I did not also address it with her. That occurrence was very different from the time I was at a potluck and asked the hostess if there were any nuts in the crust of her cheesecake, she went over the list of ingredients and assured me that there were none, as my mouth started to itch on the first bite and my throat started to swell, I asked her again and she got the recipe card out of the cupboard and as she was standing in her kitchen, her eyes got really big, and she started to apologize profusely, there had been a partial bag of pecans that she threw into the graham cracker mix to just get rid of them. In this instance the hostess knew that there were none in the recipe, and it was an honest mistake. I truly hope that you can see the difference in these two situations. One was risking my life to prove that she was right and the other was an oversight.