Every day is a new day. Fresh starts are available to all of us every morning. When you meet up with a co-worker, friend, or even a customer all of you have the opportunity to start from scratch.
How many of us have ever made progress by holding a grudge? We have no problem helping clients transition to another service provider or cutting our ties if we feel the relationship isn't healthy, but what's the use in counting the number of offenses or even saying internally that a client is "on thin ice"? That puts you on the defensive in your interactions and other people can sense when you're closed off.
When we approach our interactions as if nothing negative has ever happened, then we're giving everyone the benefit of the doubt and allowing others an opportunity to put their best foot forward. We have no control over how they'll react, but at least when we put forth our best effort, we can walk away knowing we left everything on the table.
Are you able to say the same?