I have a few that my C has put on the groups FB page:
No matter how many mistakes you make or how slow you progress you are still way ahead of everyone who isn't trying - unknown
I had a vase with 7 flowers; 1 to represent each day. If one of my flowers was to die, would I throw them all away? So when you've had a day of treats, and feel guilty and annoyed, why would you give up on the week, with 6 days left to enjoy?
Your body, Your mind, Your decision
You're off to great places. Today is your day. Your mountain is waiting, so get on your way - Dr Seuss
You don't have to be great to start, but you have to start to be great.
If it's important, you'll find a way. If it's not, you'll find an excuse.