Many thanks to everyone for all the sound advice and encouragement. I was back running the next day and Dublin City Marathon is in my sights. I just hope there are no big puddles around on the day!
Very brave and honest report Kevin, one we can all learn from. As an Ironman you have nothing to prove and as many have said here it's how you get back up after a day like that that really matters.
Good luck with the marathon training and hope you get your day in the sun in October!!!