Wonderful post. It is very important to be able to talk about our problems and depression is a common one that we tend to hide because we may feel ashamed. There is nothing to feel ashamed about. It's something that most of the people go through in their life time, whether they are aware of it or not. Depression is caused by changes in the brain chemistry. What causes it? It varies by person. I think it is important to go deep and look for the things that bother us, because often there is one or more particular problems that may have been eating us up inside and until we don't recognize the problem, we can't solve it. When that particular 'problem' takes control over us, we feel sad, hopeless, angry, guilty and also we tend to loose interest in doing things we loved doing before. The good thing is that we can defeat depression, because we are much stronger than what we think. Once you find that problem, you can start working on finding a solution for it. To answer your question, medical treatment is not the only solution, it will not help you find the problem you are looking for. You need to have someone who you can rely on and talk to, who can help you find that problem. Depression is real and must be taken seriously, however, let's remember again what it is. It is a mental health disorder which of course is 'not just in our heads', but at the other hand, it is there and let's not forget how powerful a mind can be. More powerful than a medication.

Wish you all the best.