My 26 Year Old Daughter Is A HS Teacher And

My 26 year old daughter is a HS teacher and just before the school ended, she had mono. She continued with unusual, weird fatigue (off and on), feeling like she was going to faint or vomit, feelings of panic. As her mono was getting better, she still continued with these symptoms and needs to eat to 'settle her stomach'. She became so anxious from the symptoms, she saw a psychiatrist who prescribed Prozac, Zyprexia and Inderal PRN. She is afraid to be alone, afraid to be in public, doesn't think about anything or anyone other than how sick she is feeling. She's been to the ER, and they did every test - had an ECG, multiple blood tests and nothing is showing up. She's been on the psychiatric meds for about a month with no sign of the symptoms dissipating. I believe she is suffering, but I also don't want to support this constant list of complaining. I cannot think of any test that could determine why she is feeling so sick.
She was once a vibrant young woman, funny, empathetic, thoughtful, sweet, and now she's always complaining and feels sick, doesn't want to do anything. Any thoughts on this? Thank you.