This is going to be a bit lengthy but want to make sure I give as much insight as possible. Dory is a 13 year old tabby, who I have had since she was 8 weeks old. She's a little love, and I can't imagine life without her. It's just me and my two kids in my house and of course, Dory. Dory is well loved and has plenty of cuddle and play time. Even has her own indoor cat garden where she nibbles on cat friendly greens. She's always been great about using her box. A few months ago, she started pooping right outside of her box. Tried new litters. Moving her boxes(she has two). She still continued. I figured I could live with it if it was just that. I clean Dory's boxes every day. Two weeks ago, I went to clean her box and nothing was there.I saw two spots that she sprayed right up against the wall(and on the thin carpet). I immediately called the vet to make an appointment but they couldnt get Dory in until a week later. In the meantime, I tried three different litters, moved her boxes to a different location. I also blocked off the area that she was spraying. So she started spraying in other areas of the basement(is a finished basement). She would pee on some of my daughter's soft toys(Barbie clothing, felt play food, etc)Didn't matter if I was home or not. The vet did blood and urine analysis. Blood came back great. Urine had struvite crystals and white blood cells. So we have started her on antibiotics for a UTI, and transitioning her to a urinary health cat food. It's only day 4 of the antibiotic. I also purchased 2 of the Feline Pheromone plug-ins that have been going since Wednesday. I absolutely can not have her spraying and making my house smell. I try to be quick about locating the spots to clean. Have been using Nature's Miracle. While I am at work, I have quarantined her to an area in my house with old linoleum. When quarantined, she will sometimes use the box, and then sometimes still pee and poop on the floor. I feel terrible for having to keep her in my laundry room while I am away and now at night too(She is use to sleeping with me).I'm sure its not helping the situation. It doesn't matter if I am home or not, she won't use her box. Just yesterday, I bought her a new box that has lower sides. I feel like I have done almost everything I can do. The vet said once the course of antibiotics is done, we will do another urinalysis. If after everything, she still isn't using her box, the vet said we can put her one a medicine to alter her behavior. So I am leaning towards that this is more behavior than ailment. Nothing has changed in my household. Does anyone have any other insight? Experience?