Hah! Love this. I feel your pain! Most of the school year, I teach. 3 hours of lecturing gets all of my extroversion out, so I can happily hermit the rest of the day. But in my off time, if my DH didn't come home every day at 5pm, I'd go stir crazy.
My strategies: always have something new to learn lined up. If I don't, think of something
definitely tv more often, radio on in the background much of the day--thank god for cbc radio 1!
get creative in the kitchen, clean the house
make regular play dates with friends (at least every other day), even if they are skype or phone dates
I heard Elizabeth Gilbert interviewed recently (on q, I'm sure there's a podcast) about her new book. She said my new favorite thing ever: "I realized that there is a border collie in my head who needs to be entertained at all times. Even it it's just a ball being thrown against a wall. If I don't keep the border collie entertained, bad things happen. Don't let the border collie get bored!" (paraphrasing)
Isn't that just the awesomest thing ever?! Or is it just me? lol. My takeaway from this was recognizing that it's ok sometimes to just find a way to stay OCCUPIED. It doesn't have to be lifechanging, it just needs to be not sitting and thinking and letting myself get bored. Cause you know what happens when a border collie gets bored...it finds things to do. Unhealthy, melodramatic, childish things to do. :0