Man troubles

Sooooo, I'm an aspiring author. I write mainly "adult" romance novels. Anyway, I've been knee deep in my latest project and my fiancé walked in on me writing a very steamy scene. He wanted to read it. So I let him. And now he thinks that I'm not happy with our own sex life... Sigh. Any thoughts on how to explain to him that I'm writing fiction? Lol