A review of my daily breakdown

I feel like I should put a disclaimer on this post. I love my mother-in-law. But sometimes I just can't stand her.

Almost two years ago my husband's father died suddenly and it totally changed our world. Since then Jay and I have had the same argument over and over again. We somehow have taken over the responsibility of taking care of my MIL. She is not an invalid, she is not incompetent, she is just needy. My husband accompanies her to her meetings with the financial guy, the lawyer, the accountant, etc. All because as a stay-at-home dad, he doesn't have a "real job". He doesn't have to take time off or ask his boss to go to a 10:30 meeting across town. And every time he asks her to take care of it on her own, she makes him feel guilty and he eventually caves. This is where our fights begin.
I want him to cut the cord and force her to do things for herself. Just like our son and potty training; if you want to stop wiping his butt, then he needs to learn to do it himself. He feels that this is his responsibility, his father's spirit telling him to help her. I try to tell him that his father would not want this burden for him and that he has two older siblings that could help out. So we fight because I don't want this to be a forever thing. And we fight because he gets nothing done at home when he has to help her during the day.
I do want to add a bit of snarky commentary. We are the only functioning couple of her three kids. We have a happy marriage, while her two other children have three failed marriages between them. And while its not all her fault, if you asked any of their spouses, she has added to the demise of their marriages. Yet if asked, is oblivious to her influence on her children's marriages.