She is displaying patterns of someone desperately crying out for help, but won't acknowledge or accept assistance. For some they enjoy being in this state, until people stop listening to them.
Yes there is a mental load to parenting, but that comes with being a parent. Talk to your other half, talk with the children. Get your parents to help out
She's resenting her husband for his job and being able to get out of the house. Resentment gets worse and eats away at you.Talk to him.
And it's not up to her to manage everyone elses emotions. Often people do this when they don't want to face their own. We can't control others. I think mfm needs to see her GP, every day her posts are spiralling more and more out of control. Step back from IG she almost needs an intervention