I have exactly the same symptopms. They've just started in the past month or so, but all I can find online is anxiety. I don't feel stressed at all in the day and I like to think I live a quite relaxed life. Sorry I can't help...

I have the same symptoms as you...I dont have the fear of dying in sleep ofter..But everytime i get a pain in the body, i think it is something serious like cancer...
And i read that this is called hypochondriasis...

I know exactly what your going through. I have been going through this since i 9 years old when one of my good friends died in his sleep. I am 18 now and I still get scared to go to sleep sometimes. Not near as much as it used to. I used to do the exact same thing that you did. Every night I would lay in my bed saying, "This time it is real. I am gonna die in my sleep tonight." And then i would wake up the next morning. I learned that you have to just accept it. There is no sense in getting all worked up about something that you can not control. If you are going to die in your sleep, then that is what is supposed to happen. I'm being very blunt but it is the truth. Honestly you do not have anything to worry about. The only time people die in their sleep are from seizures (which you would have to have that disease where you get seizures often, seizures don't just randomly come), overdosing on something, or if you are just old. Our bodies are built to survive. Your body isn't going to shut down because you are asleep. I know that i'm not really saying anything that can help you but just know that it does go away. You will realize that you are getting yourself worked up when it is not relevant. I hope this helped a little and i hope you get over your fear soon. I know exactly how you feel. Just hold on buddy.

Just thought I'd say I experienced what you mentioned for about 7 years. I was diagnosed with Panic Disorder. At the time I was also severely ill. After being diagnosed with Diabetes type 2, anemia, and PTSD, I saw how all these these played into each other. When I first started avoiding going to sleep, I became hynogogic. It means you're body starts to shut down from lack of sleep and your brain thinks it's asleep even though you're awake. This caused me to become psychotic, as would anyone. I was told that I could die from exhaustion. It's really a vicious cycle. The symptoms caused by illness cause psychological symptoms to worsen which caused my illness worsen...and so on.

What really helped me finally get to a place where I'm not literally anxious at the thought of sleep is Cognitive Behavioral Therapy. You learn what thoughts are behind your fears, what feelings are hidden in them, and then practice techniques to cope and overcome it.

Good luck and take care of yourself, ignore nothing... fear is real but you can get your life back.