Really? That's sad, I feel really sorry for you man.
I know I'd literally go insane if I found out I couldn't go snowboarding for the rest of the season!
Now I'm really glad I bought those Demon Soft-cap knee guards. I temporarily messed up my knee in a dirt bike crash over a year ago. All last season when snowboarding I had to wear a home-made soft cap knee pad on my right knee due to it becoming more sensitive to pain on impact than my other knee, which was fine. It's better now though, but this season I decided to buy a set of legitimate snowboarding knee pads anyway, which are much better. I've already taken a few hits in the park and have been fine!
Hope you get recover soon!