I've changed the theme of my sim three times now, and every time I change my house/landscape, she also changes her house/landscape to the same theme. And for the last house, I had renamed/relabeled my house items (more manageable for me to find in my inventory should I need to take it.), and she bought the same furniture and renamed her items with I labeled my stuff with ....even down to my dog's name lol. That doesn't necessarily bother me as much. Interior design relaxes me. It just feels like she's being nasty by blocking my view of the water. But, as the others above have suggested, I'll derender her objects.
Thanks, everyone!