How do you know when it’s time?

I’ve had cats my whole life, but this is the first time as an adult i’ve been faced with this.

i have a cat i adopted about a year ago now. we were told she was 3, but it quickly became apparent that she is closer to 12. in the last 7 months she’s declined a lot. In january we took her to the emergency vet for a seizure-like episode. we were told she had a heart murmur, a UTI, and likely CKD.

since then she has had repeated UTI’s and her heart murmur has gone from a grade 3 to a grade 4 (out of 6). We moved about three months ago and switched vets. we were told her kidney numbers are perfect, but definitely has a heart issue. We like and trust this vet a lot.

in the last week it’s been pulling teeth to get her to even eat a couple bits of her food (she eats a little more when she gets into our kitten’s food). she’s also started peeing in different spots around the house. she’s never done this before, even with severe UTI’s. She’s been sleeping most of the time and has knots in her fur around her back legs and places that are harder to reach (though she still grooms).

i made an appointment for tomorrow with the vet, but it feels like it’s not actually helping her. she just gets another infection, even with a stronger antibiotic course. (we’re checking to make sure she is actually clear of them as well).

she’s a sweetie girl, but she’s obviously wonderful at hiding pain.