I keep a "Game Journal" as my daughter calls it where I write down notes about my games but also keeps all sorts of lists, lines of poetry, what went well today, and stuff like "Things That Make Me Happy.
Journal art 50 things to be happy about list. A great way to look back and say even during that lowest time I never, ever gave up. Depression WILL come to an end. Don't give up five seconds before the miracle happens. Or 50 things to thank God for!