ESH. Your mom was being a deceptive narcissist and it's shitty and wrong to not have dietary choices or needs taken seriously. Your mom was also the one who deceived you, can we say the same for your other family members who you puked in front of? I have a really really bad tree nut allergy. Mistakes happen, so I always check my food. If someone intentionally added something I was allergic to to my food, they'd be in for a super nasty (private) confrontation. If your mom hasn't been taking your vegetarianism seriously for two years as it is, use your words and check your food. Confront your mother, solicit backup from the other family members if you can, but the puking was a step too far.