I am taking a class right now that was offered via the Internet designed by a Yale professor on the Science of Well-Being. I would encourage all to Google this course. It's free!
I am about half-way through it-- but already I've learned three basic things that are so important to boosting your balance sheet from unhappy to happy"
Savoring
Being Thankful
And the biggie (to me) Gratitude.
Besides physical exercise, meditation, taking pro-biotics, Miralax for constipation, I've added in my course work, and am "rewriting" my brain to be mindful of savoring life experience-- small or large, being thankful, and bein aware of and expressing gratitude.
Living life in the positive isn't going to miraculously cure us. We're still going to miss those life events and be left lying on the couch watching bad TV. But, if even by a smidgen, we can turn up our well-being -- tune into happiness-- it really does make a difference.