I am feeling quite depressed myself tonight. It's difficult to live in a phyiscal world and not succumb to human emotions but chemicals in your brain) are ultimately the reason for your depression. Yes, the situation is causing this, I have been let down by my best friend tonight and am on a comedown off X, meth and tranqs. It has made me so depressed and makes me feel there is no point in existance but once again if the chemicals in my brain instantly changed to "happiness" chemicals (seratonin, endorphins etc) I wouldnt care for these problems and would focus on what is good. There is always a balance in the brain, for all the positive there is a trade off for negative and vice versa. Its this mental bias that alters our moods and state of minds. The only answer to depression is to sit it out and wait until the balance turns in your favour.