I know it's really hard to open up about depression issues. In recent months, I've been trying to be more honest and open about my feelings and I've found it's helped, at the very least to make me feel less isolated.
I've heard wonderful things about Omega 3 supplements. My father, who is bipolar I, has been taking them for a while in addition to his regular medication and I've noticed his mood swings have improved a lot. I personally haven't given it a shot but I've been considering it.
There's a lot of information on the internet about the way certain nutrients affect moods and depression. Above all, eating "real" food--i.e., unprocessed fruits and vegetables--and getting exercise are important and do affect moods. When I get out and exercise vigorously, it definitely boosts my mood. Of course, the catch-22 here is that it's sometimes impossible to convince myself to exercise while depressed. Still. Do what you can, when you can. Deep breathing, walks with music, giving yourself a hug (cheesy? yes, but effective). Don't be afraid to post! There's so much support here.