Fantasy?! Help

I am engaged to my man of 5 years. I am happy in my relationship and love him with all my heart, but for some reason I have a strong desire to be with a woman sexually? I grew up very religious, and can’t see myself ever going through with it...but the thought is constantly on my mind!

I love watching women being eaten out, and scissoring. My heart is racing even typing this. I wouldn’t feel comfortable sharing this with my man..I don’t want him to believe I’m thinking of cheating on him, and I don’t want him to think differently of me...advice?

Edit: Yes, I am sexually attracted to him. We have sex ALL THE TIME. I just really want to try out sex with a woman.