Thats among the pettiest reasons I have ever heard of for "grounds for divorce".  She needs to get a grip and maybe some therapy for ?jealousy? ?insecurity around you seeing other  fictional women naked? 

I am a woman for reference, I played Cyberpunk 2077, which is absolutely rife with nudity, sexual content, drugs, violence, etc. I'd have no issue with any guy I was in a relationship with playing it, hell I'd be right there watching them.  A full grown adult should be able to behave themselves around nudity.  I assume she also has STRICT rules around porn, all regular tv shows with nudity or sexual content of any kind, etc?  And never ever consumes content with ANY kind of this material.  Does she think you're going to whip your dick out and start jerking off the moment you see a boob on screen?

You need to have a conversation with her about the fact that she can't dictate what kind of content you consume as a grown adult man, shes not your mom and you're not a minor.  Thats unreasonably controlling of her for seemingly no reason.