I felt robotic for most of last year and the year before. People around me would be smiling and happy and laughing, and I felt dead compared to them. As in, "Meh." and I even put on a fake laughter and smiles just to blend in. People noticed this of course and just found me strange. I realise now that when *I* feel dead or depressed, it's just not worth interacting with people. When I feel dead, no amount of interaction solves it - I'm just a 'dead' person around people and they find me 'off'. I mean, I still get out when I'm feeling down, but I just avoid interaction with people. Luckily my friends get the message that I don't want to talk to them. They don't get offended.
Even now if I had the choice, I wouldn't smile if I didn't feel like it. Then people would find me rude. Most of the time I am smiling naturally anyway, but on my 'off' days I try not to interact with people face to face.
Only thing I could mention is that perhaps doing something you're passionate about would help, and stop doing things you're *supposed* to do, if you can get away with it.
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I've left WP.