Good on you! Sonds like you might be right about yur incidental exercise - it's amazing how quickly all those small things add up!
You don't HAVE to go to a gym to get cardio if you don't want to. I didn't step foot in one till recently, and even then it's an aqua-aerobics class and just started boot camp, not like a stereotypical gym thing. I'm not really a gym person. As it is, the boot camp will test me.
As an example, my cardio over the last few years came from:
walking and jogging round a local track before work
Cycling to/from work/uni
Walking my dog (sorry about your pooch by the way
Badminton - does that count as gym?? I don't think so
35kg lost. (November 2005 - October 2006)
15kg gained again (as at October 2010).
Back to the drawing board - Let's do this thing!
"You can't change the winds, but you can change the sails"
"Reach out and take control of what lands in your lap"