My Disappearing Roommate

I have my room to myself this weekend. I also had it to myself last weekend. And the weekend before that. My roommate tends to leave on the weekends to visit family and friends. At least, she claims that's what she's doing. I think there may be a more interesting explanation. I think she doesn't exist during the weekend. I think a witch put a spell on her that makes her disappear during the weekend and that's why she's not here. It's clearly a much more logical explanation than that she's visiting friends and family who live nearby so she can sleep in a real bed and eat real food. She claims that she will be here next weekend. Maybe she gets a reprieve from the witch's spell once a month. Maybe she's figured out how to break the spell. Maybe there's no spell at all. I guess I'll find out.