Difficult decision, and I have to say quite sensible to leave it a while to make it. You wouldn't want to quit and wonder what might have been if you'd carried on.
You set out to cycle for a year, got hit by a moped, got back on your trike and carried on, had to change your diet completely, got back on the bike and carried on, moved into the next year after you started, got back on the bike and carried on, and only after plenty of thought did you make the difficult (and probably correct) decision to stop. You still claimed a UMCA record and no doubt have some awesome memories. Might even have inspired a whole generation of new attempts on it. Enjoy a rest.