Well, there are certainly a few fanciful ideas and fertile imaginations above.

Boggs' version about a hooker?, Red apple juice = menstrual fluids?, Adam & Eve and the one eyed trouser snake? all good fun.

Surely a straightforward end of relationship song. He tries to give her a life of comfort but she still acts in a way that he doesn't like and threatens to send her back home on pay day. She asks "Who'll rock the cradle when I'm gone?", he replies "I'll rock etc"

Some versions include "some rounder came along and stole my jelly-roll"
so possibly a little cheating on her part was the reason he couldn't get along.