There is a new book coming out later this month, you can read about it here. I found this quote rather meaningful from the article:
"Optimism is not about the future and it’s not about the news: it’s in my power. It’s about how I react to events, the moment they occur. It’s in the mind. The real optimists, the people I admire the most, have a set of beliefs and routines for reacting that keeps them happy and alive".
The Optimist: One Man’s Search for the Brighter Side of Life by Laurence Shorter