Although I agree with the ideas of getting exercise, talking to a therapist, etc. I want you to see a doctor. A real psychiatrist. What is the big deal with seeing a professional who deals with this all day every day? One in four people will suffer a major clinical depression at sometime in their life, and there is no good reason to "tough it out". Some who try that, do take "the only way out". Clinical depressions can be successfully treated with medication, and given the right ones at the correct dosage, you will fell much better in several weeks. I have much experience with this kind of problem, and you must look at it in the same way as any other chemistry problem in the body. The brain is an organ, just like the liver or the thyroid, etc. Those organs sometimes malfunction, as any one of our organs can, and treatment is necessary. Taking medication for depression, or a more serious disorder is really no different than taking insulin for diabetes. If you need it, then take it! It amazes me that people so frequently think that these conditions are treated with recommendations like "get out and see a movie" kind of things.
I agree that mild depressions can be managed with diet, exercise, talking with someone who cares, etc. etc. but I have ready many of your posts, and frankly, you seems to be suffering from more than a mild to moderate depression. Please, please, get some help.