Snap, I hope it will be of some comfort for you to know that I have a good friend whose husband had this surgery this past summer, is well on his way to recovery, and is intermittently a bit euphoric about not being in severe pain anymore...it'll be okay, kiddo. AND you will still get to do your marathon.
"My predominant feeling is one of gratitude. I have loved and been loved;I have been given much and I have given something in return...Above all, I have been a sentient being, a thinking animal, on this beautiful planet, and that in itself has been an enormous privilege and an adventure." O. Sacks