Is there anything physical you can do to help distract yourself? I've been reading that exercise is a very good way of coping with depression, better if you can find something you enjoy doing regularly. It releases endorphines and burns up tense energy so you feel calmer and more peaceful afterwards. Since it sounds like tension and anxiety are your biggest problems, this might be a good place to start.
Harder to do, (trust me, I still struggle with it regularly) is to try to stop approaching situations with the expectation of failure. Cautious optimism is easier than just assuming the best in all cases. It's a little like wearing a bike helmet. You generally assume you won't need it (optimism!), but if you hit a stick and fall off, it pads the impact rather than you just smacking face-first into the ground (but cautious!).

That all said, we're here to help each other, so keep posting and we'll try to talk you through things.