Do or Die....

Hello! So here's a quick run down of the story
Around a year and a half two years ago, I went from a healthy 127 lbs to a very thin and very weak 96 lbs (I'm 5'9) in the span of a few months, I saw a ton of doctors and came to the conclusion that I was ignoring the fact I didnt eat enough. Now everytime I eat, I feel extremely nauses, to the point I have to spit the food out.I'm extremely worried what's gonna happen if I dont put the weight back on...so here I am!
Any advice welcomed!