Roommate decorating my house

So I own the house, it’s fully furnished with my own decor & furniture. I had a new roommate move in like a year ago - I rented her a fully furnished room. And I immediately she began decorating my kitchen and living room with some of the ugliest decor I’ve ever seen. At this point it’s made my home look cluttered and I hate the way it looks. I’d like to tell her to remove her decorations, as I’d like a more cohesive and neutral aesthetic, as it was originally. I don’t want to offend her, but this is my house and I only rented her a room.

What are your opinions?