I slept with a black guy when my boyfriend and I were broken up. Now he thinks I am into black guys?

I had a drunken night and made the biggest mistake. I slept with a black guy and now he thinks all black guys are eye *&^%ing me and I am eye *&^%ing them. He think I want a black guy and it is ruining our relationship. What can I do to prove to him I am only into him?
I slept with a black guy when my boyfriend and I were broken up. Now he thinks I am into black guys?
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