Dear Chris,
Best wishes to you, your father, and your mother, dealing with her dashed hopes of being the one to both help him and keep you from this decision. I hope you all manage to hold each other tenderly as you all embrace the issues, fears, and joys of where you've found yourselves.
Empathy about the paucity of good long term studies despite the 60 years of living donor surgeries. The risks of your life activities will be only slightly modified by both your setting forth on this path, and by actually undergoing surgery to donate, if you eventually do. Our existential risks are many, diverse, and poorly understood emotionally even for those who delve into the topic and learn the amazing realities, so different than our typical day to day worries. In particular, the best conceptual model I've encountered, still only minimally supported by evidence, separates the surgical risks, relatively well studied and as true for us as any patient, the emotional risks, unique and possibly unquantifiable, and the nephron mass loss, approximately equal to one's kidneys aging 20 years.
The surgical risks you can research, and I urge you to do so, especially the variety of complications and indirect effects, during surgery and the peri-operative period as well as long term. Having a plan can help you and your family prepare practically and emotionally should you be unfortunate enough to experience any of them. No plan, no data, no other person can tell you what your own emotional reaction will be or should be. In advance, one can only do one's best to be informed and hope. As for the the cost of the gift, one cannot know if End Stage Renal Disease will be the limiting factor in our spans. Kidneys go to the grave fully functional in too many cases, and kidneys recovered from even elderly deceased donors grant years of improved quality of life to the majority of recipients every year. Will giving up 20 years worth of the total nephron mass you have mean you'll be a candidate for dialysis or transplant sooner than you might have anyway? Will that be in 20, 40, 60 years? Will technology have changed by then? All unknowns that you have to make peace with to get to yes or no. Again, best wishes for you all.