Okay, quick story:
I had chicken pox, but no one explained what the symptoms of this might be. I was in second or third grade. Suddenly, there were these itchy bumps all over me, but I did not feel especially sick. I considered this carefully and decided, "Oh. I'm dying. I guess I'll just die. I don't want to worry anyone with this, my imminent and untreatable death."
After days of this, possibly for unrelated reasons, I went to the nurse's office. I lifted my shirt, and she unfurled an actual profanity over how poxy I was.
So, I didn't die, but I do have mental health problems. Seems like someone could have diagnosed that, too.
(I also spent years of my youth thinking I had terminal breast cancer, but I was not willing to tell anyone. I had a bump in my chest which I, in a fit of genius, figured I could press in and make it stop being a tumor. Turns out it wasn't a tumor, just a bump. In my adulthood, I actually had a breast cancer scare and decided I might die, but at least I told people about it! I was fine that time, too. Turned out it was just a bump.)