I crated Layla when I got her then stopped crating her and we had the same situation, of her just going.
I went and got a bigger crate and started crating her again at night and during the day while I am at work. Then when I was home I kept her close to me either in the same room or if I was preoccupied I tied her leash to my belt loop and kept her close, she has now earned back not having to be tied to me, and I leave her out of the crate when I go on short errands.
If you are not wanting to crate, have you thought about applying the same rules to a bathroom and adding a baby gate?
Layla- WGSD mix- Shelter survivor
Lionheart- mean fat cat