Living in a state of constant fear and apprehension.

Hi all. 55 F here. I was just wondering what being in a perpetual state of fear (with some anger thrown in) do to someone's body and mind. Could it make you more prone to inflammatory diseases (I have colitis)? I spent much of my childhood feeling scared. When I was a teenager, I went through a phase of waking up at night feeling absolutely terrified, convinced that there was "something" out to get me, hiding in the darkness. I would have to put the light on for the rest of the night, and my fears only dissipated with the coming of daylight. It was horrible.

I have developed what seems to be medical PTSD after really struggling with my health this year and being in and out of hospital. I am terrified now of going back into hospital and feel frightened much of the time. It's exhausting. How best to deal with it?