So I can't tell you where to look, but I've found that the good moments are hard to recognise when you're approaching rock bottom. Notice them when you're feeling better and make sure you remember them for when the days get dark again.

For me it's moments at work, travel experiences, times spent with close friends. And maybe they are fleeting moments, but I would still say I was happy in those moments and I know there are periods in my life where I had more of those moments than of the depressing ones.