Having dreams about another man...

So I’m married, happily. I love my husband and I don’t want to be with anyone else. But I keep having dreams about a man I work with. They started out flirty, but last night they got sexual. And the weird part is I don’t even like this guy in real life. He’s a racist know it all asshole, I’d really love to punch in in his damn face. But then I keep having dreams of being with him. I feel like I’m cheating somehow even though I haven’t actually done anything. I don’t have dreams about any other men, it’s always this same guy. Any advise on how to not have dreams about this asshole?