I grew up on jay-z, tupac, biggie, etc…
so whenever I heard the word “regret” i thought of the Jay-z line “Gotta learn to live with regrets”
after a while, my regrets went away. because everytime i heard the one “regret” i thought of the jay-z line “gotta learn to live with regrets” and it trained my mind to live with regrets
mantras are good
I know a few the main Hindu, Buddhist and Jain ones 
Yes, I have phrases set aside in my mind that I repeat to myself when needed.
I used to be such a simple girl, and I liked it like that. When my mind starts thinking crazily I think to myself “think simple thoughts”. It’s cool cause its like something in me tells me hey look out, think simple- you’re over doing it!
Hope that makes sense.
Thanks for the post!
You named some great artists too 
I did transcendental meditation for a while. I got a mantra from them.