I think if you’re going to get PTSD from killing an animal then you shouldn’t eat meat. If the act is so traumatising for someone then clearly they have some kind of conflict about it.
If you already have PTSD fine those people get a pass don’t want to cause more harm but that’s an incredibly small subset of people
I don’t think people who are incapable of killing an animal (mentally not physically) should be allowed to eat said animals
I’m a vegetarian and am perfectly healthy, on the higher side of BMI, regularly go to the gym and have above average muscle mass so the argument that you can’t get the nutrients you need is bullshit. I’m sorry about your family member though that sounds like a full blown eating disorder, not veganism