JAK, It does seem that the care of an ill person usually falls to the women of the family, doesn't it? I'm not knockng men at all, because my dad has always been one to those rare caregivers.
I'm sorry that you and your SILs are not receiving more help with MIL, but you are right you will know that you did the right thing and have no regrets. I wish I could give you a solution to get more help, but we know it would probably fall on deaf ears.
Hang in there my friend, you will have many stars in your crown.
Hugs, Yoyo
Life's challenges are not supposed to paralyze you, they're supposed to help you discover who you are. -- Bernice Johnson Reagon