Raschaverak Wrote:I do meditate as well, however it doesn't seem to help. I guess I can only change my behaviour and my thinking pattern with acting, doing things differently in same situations, or doing different things, thus reassuring the positivity in it, and in hindsight, on the sub-conscious level, creating the seeds for positive thinking ("Oh I did this that time, how cool , oh I acted this way in this situation, how nice, ect.) This is the only way I can think of, I know myself this much, that I won't be able to just snap out of the negativity by deciding upon it. I need to act - without too much thinking 
Have you tried any of the other advice people gave before, e.g. exercise? I think there's a lot more to depression than most people think, and it could just be a symptom of all sorts of different imbalances in the body. You probably stand the best chance by improving everything you can - negative thought patterns, stress, nutrient deficiencies, dysbiosis and chronic infections, lack of exercise, inflammation - there could be a lot of factors at play. It may seem like it's all in your head, but if your head was flooded with serotonin, you'd probably feel slightly different about that, and improving your general biochemistry is likely to improve your brain chemistry.
The gut-brain connection is an interesting one. A large part of the nervous system resides in the gut and the majority of neurotransmitters are created there. There have also been some interesting experiments involving "bacterial therapy", like
this one. If you suffer from GERD, indigestion, bloating, gas, bowel pain, constipation etc then resolving these could be very helpful.
Fabrice mentioned vitamin D before and he's seriously right about that one. A deficiency is linked to more diseases than you could name, and it's extremely common,
if not epidemic, nowadays. A recent report said 1 in 4 are deficient in England. If you can get a serum (25OHD) test, you might find the results interesting.
If you want to resolve any chronic disease, you've got to take on a big role yourself. Medicine isn't in the business of cure or prevention. It can take a lot of investigation and experimentation on your own part. Keeping up-to-date with the research and reading about the experience of others gives you clues and ideas to try. The most important thing is not to give up.