Stoicism and AA. I have found combining Marcus Aurelius, Epictetus, with The Big Book and the 12 and 12 to absolutely amazing and spiritual growth productivity is through the roof.
Retraining my brain to process life differently while attending meetings and working with others is so incredibly rewarding.
If you want a MASTER COURSE of Acceptance in your daily life, buy a copy of Marcus Aurelius- Meditations. You won't be disappointed.