I once took six months off from training. My first day back I tested my maximum amounts and surprisingly was able to lift about 10% more weight on all motions. Go figure!
Personally, wouldn't worry about it too much. There's good feedback here regarding protein an calorie intake. Plus, you'll need good nutrition for surgery recovery.
Studies show that a special diet high in protein BEFORE an operation speeds recovery. Naturally, lots of protein AFTER is paramount. There may be times when you just won't feel like eating but you gotta anyway. Find a tasty protein powder.
In the hospital, they actually feed glutamine intravenously while recovering. (Google "wound healing," "Pre and post-op nutrition").
Plus, creatine and BCAAs have nootropic benefits, improving brain function, even if you're not working out. (maybe it's a time to train the brain?)
Find a positive perspective... God's giving you an opportunity to grow in other ways. Find'em and have fun!