The same is true for me. Damn typing classes would mark you down if you didn't two space, so that drove me into two spacing everything, as well. I've been trying to push myself into single spacing for a while now, though...It's tough.
I can't remember what my college course required because I only had to go five or six times to prove my proficiency. (Yes, my university's computing program required a typing course because they had students that couldn't touch type.)