My season's over.

So, I fell off my bike a week or so ago and today I found out I'm having surgery for a torn meniscus. I know it's not a big surgery, but I am so bummed. I had an AWESOME first tri earlier this month, and had even registered for another one on Sept. 11 (which I plan to go to anyway, to cheer on my fellow BT'ers...) But in the meantime (pre-op), I can't run OR bike (because of the location of the tear...) and my access to a pool is about to become really limited. She even told me not to do any karate but I will get tough and just do some slow kata (I CANNOT give up karate). Anyway What can I do to keep myself "in shape" if not cardiovascularly, more muscularly. Basically I want to make sure I'm ready for ski season here in a few months and I don't want to lose all the strides I've made in the last few months. I have an exercise ball...anyone have any succeess stories for me? And how can I keep myself from getting totally depressed? Like I said, I know this surgery isn't a big deal, but I'm just feeling frustrated tonight. Thanks, folks!