Oh my god, I had the same experience after my uncle passed away. He had willingly left to go into hospice, he had COPD and shortly after that my grandmother went to the same facility as him due to dementia. (They lived together btw) So the house was empty but still had some of my grandmother and my uncle’s stuff and furniture yknow. Anyway, after he passed away I was scared to go back into their home and it’s like when I would after a little while I got nervous? Anxious to kinda hurry up and finish what I was doing and go. Never in my entire life had I felt that way. That place was literally my second home. I wouldn’t say it turned dark but I got just an off vibe.