Our hearts have an infinite capacity because they have been created to love an infinite God. If we love anyone or anything more than God, we will always want more of that person or thing, and the more we get the less satisfied we become.
http://www.peninsulachiropractic.ca/physical
It's about feeding your brain with the right things to improve your resiliency and ability to over come - here's some great research on Placebo https://www.scientificamerican.com/article/the-power-of-placebo-how-our-brains-can-heal-our-minds-and-bodies/
"and you will know the truth, and the truth will make you free" John 8:32