I also talk to myself when alone. I ask myself questions and answer in a different voice. I put this down to having kids. They're pure noise all day, so when they're gone I find the silence stifling and need to fill it.

And the other thing I do when alone is dance around the house rather than walk. Well, not dance exactly, but perfrom aerobic moves. I'll grapevine, sashay, box step and easy walk from room to room because I feel so FREE!