To clarify, I'd like to add something to the above lovely and loving thoughts from people who care about you, Mickey.
In my earlier post I did not mean to imply that depression strikes for absolutely no reason. I'm sure there are numerous reasons a person may become depressed, certainly including home environment, early experiences, traumas, all sorts of things. No, I was speaking from the outcome of an experiment I just recently concluded, wherein I decided to try going off my longtime medication. I had every reason to try the experiment. I had developed a philosophy from my reading which seemed to be working well for me in combatting my depression. So I very gradually tapered off my medication and truly expected to at last be able to function without it.
Sadly, once it all had left my body, even with my greatest efforts to "not think", I crashed. I wept, I cried, I wanted to die. I felt there was no hope and there would never be any hope. Finally I admitted to myself that my experiment was a failure. Two weeks ago I started on a small dose of my medication again and am already doing better. So in other words, no matter how hard I tried to control my depression through my thoughts, as the Cognitive people say you should be able to, it seemed there was a chemical element to my depression. That at least was my experience.
So indeed depression can be a tenacious and complicated beast. As a result, help for you might come through many avenues.