The best thing to say to him is “Goodbye, we are done!” or just “Thank you” because he broke your heart and he doesn’t deserve anything from you. You should also tell him that you have moved on with your life and you wish him well.
First, tell him that your glad he showed his true colors(being a liar) when he did, so u didn't waste precious time w/him. Second, make sure he understands where ur heart/mind was at in the relationship. Finally, Don't linger,(it will give him time to come up w/ a more-than-likely hurtful rebuttle) just turn and walk away, or if your on the phone, Say "I wish u better luck next time, I'm sure you'll get it right someday, please don't contact me again. Good-bye." And disconnect for good! BE STRONG the 'right' man will come along.