It's hard to be completely honest because you care what she thinks about you.
On the other hand, from an earlier comment you made it sounded to ME like this is a really, REALLY good woman you have and someone you can (and should) be honest with.
Now ... it is completely natural that seeing something titilating makes you crave sexual behavior. That's how you were designed.
So now, are you saying your wife took off her top and you felt the urge to touch them? Frankly, dude, if that's the case, if your wife took off her top and you felt the urge to touch them ... isn't that what we're shooting for? Who cares, then, if your horniness was triggered by a scene in a movie? You wanted to engage in a sexual act with your real, actual spouse. Isn't that what we want? It sounds like you're overthinking this.
So, what the fuck is wrong with you? Nothing in this scenario that I can see. I guess it's not really clear what happened here. What upset her? Did your sexual advance upset her? Did talking about your fears for your reason for wanting to make the sexual advance upset her?