I've definitely been on both sides of the ghosting thing, its hard to figure out why that becomes the easy choice. Maybe its just that people are hard and staying home alone is easy? Or maybe ghosting the person allows you to avoid any negative emotional consequences in the short term? I suppose you could try to reassure the person you aren't upset with them.

For me I've noticed too that when I want to be left alone is when people won't leave me be, and when I'm trying to find someone to do something with there is no one, so maybe it has something to do with expectation.