I agree with everyone....but I will say that I missed a wedding that I was invited to be in for my ironman. BUT in my defense, I signed up 1 year in advance (and pretty much started training!!), and they asked me about 5 months ahead of time. The bride told me that she LOVED that one of her friends was bad s$$ enough to do and Ironman, and she totally wanted me to do that instead. Granted, Ironmans are really really expensive, planned way ahead of time (nearly impossible to replace because they fill up a year in advance), and I called to have an open and honest conversation about the situation.

I agree with everyone you are making the right choice by doing a different one, but I thought I would fess up and say that I didn't make that choice, and it turned out ok