It is your house. If I were a guest and my friend went to the bathroom I wouldn't go looking for her. The toilet is a place I want my privacy because I have IBS.
I think if you are trying to place meaning on them not looking for you that is not there. They didn't quit caring for you and they didn't quit being your friends. I think you are being very sensitive. Is that common for you to interpret your friends' behaviors in a negative way?