I think Shanann was motivated by multiple factors.
She was heavily involved in several different multi level marketing programs. She was currently deep into Thrive (the vitamin patches), but had also tried her hand at Amway, ItWorks!, LulaRoe, Younique, Poonique, Thirty One, Origami Owl, and probably others, too.
MLMs encourage reps to use social media to recruit new members, and to”build their personal brand.” Shanann’s personal brand was all those vids of her, the kids, Chris, outings, trips, etc. It seems like they lived their lives more on social media than living just to live. It really looks like she got addicted to posting it all online, and couldn’t stop. So much of it looked staged for SM. Pretty soon SM became her life.
It seems like Shanann needed to feel that her life was good enough to share online (this made her feel validated), so even if aspects of her life fell short, she artificially staged it to make it seem better than it was.