While studying at art college a man whose nickname was Humpty used to frequent a bar used by students but not exclusively by students. This guy was well liked, in his early 60's and he didn't mind being called Humpty and most evenings on the way home from work with his wife he would pop in for a pint dressed in a suit. On Friday and Saturday nights he would come dressed as a woman he didn't do it well and over the year apparently has been attacked on his way home a few times. He/She was a really nice person to talk to, I never had the guts to ask why.
I am not sure why he was called Humpy, It could have been liked to Humpy Dumpy, Dictionary meaning-A person or thing that once overthrown cannot be restored.
Or it could be something to do with the cannon in Colchester called Humpty that fell of the wall and could not be put back together