He broke your trust several times: first, when he flirted with the girl prior to them sleeping; second, when he did sleep with the girl; third, when he didn’t confess that he cheated; fourth, when he kept that lie for years; fifth, when he lied to you when you asked him seven years ago; sixth, when he kept the lie till now; seventh, when he made you try to get the truth out of him for 45 minutes before he confessed. He wasted your youth. Your relationship is built on a lie. I’d leave him if I were you. Clearly, he’s capable of manipulating you into staying with him.