Is it normal to get tired of a fetish?

Like I've said before, I have a major fetish for women who don't wear underwear under their dresses/skirts. It is such a huge turn on for me. I always ask my sex friend to wear a dress or skirt without underwear before meeting her for sex every weekend. It's so sexy knowing that all she has to do is lift up her dress and allow me to simply put it in her. She gets so turned on by it that she keeps her dress on during the sex which is fine and all, but after a while I'd like to see more skin than just her bare ass and p***y. I wanna see her bare breasts bouncing up and down while she's on top of me. One time I asked her take off her dress, but she didn't want to. I guess she was so into the sex that she didn't want to break the rhythm by stopping a few seconds to take her dress off, which is understandable. As much as I enjoy seeing her pantyless under her dress or skirt, I feel like it's been done to death, and I wanna try something new in the bedroom with her like asking her to be in just her bra & panties, or totally naked. Like I said, I wanna see more than just her bare ass and p***y. There are even times I fantasize about her dressing up like Kitana from Mortal Kombat, or Rachel from Ninja Gaiden. So is this normal to feel kind of burned out or tired from a fetish? I mean I still get the urge to wanna see her pantyless under a dress/skirt, but at the same time I wanna try something different and step out of my comfort zone.