Thank you Alex for writing this. I'm going through a somewhat similar fight as you do, with relapsing depressions, social phobia and extensive anxiety towards the smallest things in life. This shit has been going on for about 8-9 years or so, as far as I can tell. It's a real bummer. I guess it's hard to grasp for people who's not been there, but that's okay. I'm now in a CBT-program, taking some antidepressants just to stay above the surface, trying to change things one step at the time.
At the moment I'm thinking about leaving my current work on a top design agency for something that fits me a bit better, a place with a little more warmth to it. Leaving my "dream job", accepting a smaller paycheck is not a big deal all things consider. It was really hard to accept at first, but now I feel confident that it's the right move for me. I just need to find passion for my profession again, for gaming and other free time interests. The pursuit of happiness, I guess. A good thing about mental illness is that it forces you to find happiness based on your own conditions. And when you're happy and experience good things, you know to really appreciate and cherish it.
Also, many thanks to the community and staff here on Giant Bomb. I Don't really know anyone here, I'm not very vocal in my presence on the boards or in the comments either. But I still feel like I'm part of something. In the toughest of times, this site has in many ways been a sanctuary to me.