It is great that you are getting some benefit from positive thinking.
Thanks for reminding me of the concept. It's something I have had to re-learn many times in life; that reminding yourself that positive outcomes are possible and setting attainable goals are a good way to get there.
There have been times when i have had to "lie" to myself, telling myself that if I stuck with a goal, that I would have a good outcome. Generally this worked. The outcome may not have been exactly what I was aiming at, but it generally worked well. Eventually the deprression lifted and I was able to function. When I have dwelled on my mistakes and predicted only failure, I have been less inclined to make the effort that was needed and, of course, I failed.
A positive outlook is valuable because it helps you keep going. It gives you energy to make it closer to your goals.
Good luck.
_________________
Never let the weeds get higher than the garden,
Always keep a sapphire in your mind.
(Tom Waits "Get Behind the Mule")