Foodpump has brought up the same thought I had. A hospital or nursing home or other environment where your interests can be best put to use would seem to be a better fit for you. They generally offer better hours and benefits, etc. as well. So you can still cook but put out food with high nutritional value that is also tasteful and attractively presented. And all while enjoying the benefits.
It may be that the chefs you have interviewed with saw this and did not bother to tell you. You've interviewed many but no offers. Obviously I don't know you or the places you've interviewed or the chefs you've interviewed with. But I have worked in plenty of fine dining places. So If you are not interested in nutritional foodservice and you really wish to continue to try and get in to fine dining, I have a suggestion.
The most important thing a fine dining chef wants is for someone to show up punctually, work hard at their responsibilities, do what they are told in the way they are told and be willing to do any job that needs doing, from mopping to plating to prep to cleaning the grease trap. That is the essence of interviewing with a fine dining chef; getting across to him or her that you are a hard worker who can follow orders without complaint. How much you may know about food preparation, sanitation and nutrition is a second or third concern. Whatever you prepare will be done according to the chef, down to the smallest detail. It really doesn't matter if you notice dirt no one else seems to, can figure out the nutritional value of the creme brûlée or have six better ways to manage things. .
You posted that your top priority is safety and sanitation and after that it's making nutritious foods. While those are laudable goals, in a fine dining interview you need to get across that your top priority is listening and following the chef's orders. Period.
As Flipflopgirl said, "work hard and fast and clean and smart." You show your concern about sanitation by the way you work.
While working for the fine dining chef, you pay attention to how to keep on top of your mise-en-place, how to get along with others, how to work fast and clean and hard under tremendous pressure. You pick piles of thyme leaves until there is not a single stem left, you french lamb racks endlessly, filet lots of slimy fish, clean fatty, bloody tenderloins and learn how to cut them into precise weights. You learn how to cut vegetables in precisely measured shapes and sizes, very quickly with very sharp knives without cutting your fingers off. You peel shrimp and potatoes and asparagus for hours and hours, over and over, without destroying the product or creating excessive waste. You do what is required of the station you are assigned to. You do it well and you do it well every day. You keep your mise-en-place clean, organized, wrapped and fresh. You work until your arm feels like it will fall off. You get burned and scraped repeatedly.
When service is over, you clean your station, help others, put things away you did not get out. You then go home. You do not offer ideas and opinions and suggestions about how the menu, the kitchen or the nutritional value of the food can be improved. Your back, feet and hands will hurt. You will be very tired, feel very greasy, sweaty and disgusting. Your thighs will be chafed and sore. You will be very upset and depressed because you screwed up in the middle of service and caused a table to be late and the chef was not at all nice about it. In fact you're quite certain the chef hates you, especially because he or she rarely speaks to you and when they do, it's more direct and blunt and doesn't seem very sympathetic. You can't remember the last time you got a compliment.
In the middle of all of this, you will realize how little you are getting paid for all the intense, hard pressure you put up with, the unreasonable demands of the jerk of a chef, the frighteningly fast abilities of your coworkers, and the terrifying need to keep your head together despite wanting desperately to cry and scream at everyone.
You will not complain about any of it to anyone you work with, ever. The next day, despite knowing how inadequate your abilities are and how aggravatingly stupid the day will be, you will show up for work, put on a big smile, say "Yes, Chef." and do the whole insane activity all over again.