sorry to hear this - I do suffer from depression and didn't really realise it til a friend had had enough of my moaning, indecision and breaking down into tears all the time and told me to go to gp and get checked out - lo and behold I was.
I personally have found starting a meditation practice and various other bits of buddhist style wisdom in my approach has helped me enormously. Anyway, enough about me
check out this book - it's where I started, it isn't religious or philosophical in any way but i honestly think it would help everyone who suffers even a bit to read it and take on board some of the gentle approaches it suggests
my best advice would be - go easy on yourself and be kind, don't ask too much of yourself...rest and just try to have the energy to do what you need to on a day by day basis
good luck