1. You really are the clean one.
  2. The other side of the bed is firmer.
  3. It's lonely and scary alone at home at night
  4. There's noticeably less towels left on the bathroom / closet / bedroom floor
  5. She gets far more personal mail then you do.
  6. You can watch what you want on tv, but it's no fun.
  7. Popcorn for breakfast totally acceptable (actually it is when @jennikonner is at home as well.