My X did the same thing back over a year ago now. I refused to go get him. I was sick and paranoid all day at work, and when I got home he wasn't there. I eventually called the treatment center and they told me he went back in. Apparantly, he put my name on his "ok to give info to" list. You should maybe try to call there, if he truly didn't leave you could save yourself a whole lot of worry!