(image via jesuisley.com)
I find it easiest to be optimistic when you have a firm foundation and meaning in life. Everything else is just circumstantial. Anything that goes wrong is an opportunity to grow and learn.
Three personal examples:
1) During college one of my friends shared a paper about the point of life is to grow. To grow is to live. There are different methods of growing–some people explore, others establish roots–both are good methods to mix and match.
2) After college I was thinking about what I wanted to do with my life. I decided on a life goal: To always be learning and to share what I learn with others. That gives my life a mission statement that I always cling to.
3) My faith in God. This is by far and away the most important part of my optimism. When all is going wrong, I know that God is there and He loves us more than we can ever imagine. I pray for greater understanding to get glimpses of his love for us.