So what can you control?
That's an easy one to nail down, but a hard one to live.
I can control MYSELF, my choices, actions, reactions etc. That's it.
I can't control other people, what they do or say or think or feel or choose.
Trying to control anything beyond YOU is what we call "Crazy-making" behavior because it will, quite simply, make you feel crazy.
Accepting that the limits of your control end with where you intersect with the world creates "Serenity." Serenity is good. We like that.
Mull this over for a bit.
