Sorry

A word used to convey to others that you recognize that you have erred and will make a conscientious effort to not do it again.

"I'm sorry I cheated on you."
(5 minutes later)
"OH Look at this hot chick on Tinder"

"I'm sorry I was late yesterday, I promise to be on time today."
(Later that day)
"Sorry I'm late, I lost track of time."