Where did you get the asinine idea that she has 40% of the time "off" when her husband is home? You do recall that adults have other obligations, yes? I highly doubt that for 40% of the week she's sitting on her ass eating milk-duds. God forbid a mother actually spend time on herself! And oh man, she should totally feel lucky to be this kid's sole provider for "months on end" because when her husband is home, she's sitting around watching The View. How entitled!

Her update indicates that this woman knew the arrangement. You can believe her or make up some evil backstory to prove how awful of a human being she is but I'm not looking to vilify anyone pointlessly so I'm going to take her word for it - the friend knew the trip was a 3 hour drive to begin with. How in the fuck did this person expect OP to be home so early with such a long drive? I'm an adult though so I would have said, "Hey, I kind of bit off more than I could chew so if you could skip the morning hike and come home, that would be great."

Communication needs to be taught in schools, so many people just suck at it.