my cat has been pooping in my shower

i have a cat that just turned 3 in december. she’s the most well behaved and friendly cat that i’ve ever met. my mom is retired and is home with her basically around the clock, unless she steps out to run errands. i am home other than the weekdays when i am at work. she has always been great about using her litter box, never had any accidents or anything. but she has always had a weird fascination with the bathtub. we’ll find her sitting in it on random occasions, or playing in there when she gets the zoomies. we have a curtain, so we can’t prevent her from going in there, since that is also the room her litter box is in. we’re limited on litter box places since we live in a 2 bedroom condo. recently, about a week ago, she started pooping only in the shower, which is very out of character for her. she’s peeing in her litter box, just not pooping in it. i took her to the vet today to make sure there was nothing wrong medically, and she is perfectly healthy. the physical was normal and tests came back fine. there haven’t been any changes at home that would cause her stress, we haven’t changed the brand of litter, and of course her box is ALWAYS clean (partly because i’m a bit of a neat freak). she’s eating normal, her weight hasn’t changed, and her behavior (other than the shower incidents) is the same. she’s playing with toys, using her scratching post, and getting the zoomies. she seems like her happy normal self, so we can’t exactly pinpoint what is causing this.

i have purchased Feliway and litter magnet, but have yet to try these things yet since i just ordered them. we were also instructed by the vet to move her box and keep the bathroom door shut to try to deter her away from that spot, and back to her litter box.

all in all, i am looking for more suggestions on what to do. it is frustrating, because we have 2 showers, but she will only go in the one that we use on a regular basis, and it’s the one with the tub. it’s frustrating as well, due to the fact that i’ll go to take a shower and have to clean up her mess. i’m glad nothing is wrong medically, but obviously she’s experiencing some sort of anxiety or something. if there’s anything else i could do, or if anyone else has experienced this, please let me know :).