Welcome to the forum.
I suspect that if I was to ask you what was specifically wrong at the moment, you would most likely answer "Everything", and then provide a very long list of examples.
I have found that this "Everything" is actually the key to the solution of pulling myself out of depression. By making a small improvement in how I feel about one small thing, gives me enough of a boost to make a small improvement in another small thing, and create a virtuous spiral, rather than the viscious spiral that is at the heart of depression.
My brother (who also suffers from depression) once said to me that it was OK to live at the bottom of the pit, because he knew that nothing could get any worse. However, he has since turned his life around, and is now married with two beautiful kids. He has a new saying, regarding his wife - "Every day I grow more fond of her".
I have a couple of recommendations for you:
Start reading the Depression Learning Path, which can be found from the Home page of the Uncommon Forum site. I found it very surprising, but also very illuminating, and a great help.
Start your virtuous circle by making some small improvements in your physical environment:
Eat well and regularly - three meals per day, every day (I keep a stock of breakfast cereal bars - as I am always late in the morning).
Get some regular exercise - I find that taking long walks works for me.
Do some tidying up at home - once you have done a bit of tidying, try to create a system that will make it easier to keep that part of your life in good order.
Finally, I would suggest that you try to offer advice to other people on this forum, as I have found doing so helps me to understand my own depression better.