I'm also not a big fan of using drugs for behavior, if you can accomplish what you want with training. It does sound more like "tired" than anxiety to me too. About twice a month I've taken Charlie to the dog park...he really zonks out on those days when we get home.
If she's playing with 4 different dogs a day, 6 or 7 days a week, I would think that's enough "dog time". Unless you really want to own a second dog, I wouldn't "get my dog a dog". When would she ever get a rest?
I'd be willing to bet that you will see her "energetic" side by keeping her with you on a day when you're off work!
