I too am the caretaker of my husband with stage 4 colon cancer, and not reacting well to the new chemo drugs he has started. Your husband is in a situation he doew not need to be in now. His energy needs to be spent fighting this cancer and making himself as comfortable a life as he is able to. Perhaps the time has come for him to make some simple changes such as getting a guardian to deal with the caretaking of the other adults--you can look into this through the senior services office in your county.t is a cost free service that will be assigned through the court, and they are very understanding.
As for the daughter and perhaps other family it is time for what I refer to as "the come to Jesus talk" and tell them straight up what is happening inside your husband's body and what the cancer is physically/emotionally doing to him, and that he will NOT be taking care of anyone from this point on and they need to think about what they can do for him for a change, and if they can't get with this program and only this program then they need to stay out of the way his fighting cancer. Also slip in that you are not available either as your priority is caretaking your husband. It's so hard when family cannot accept or even acknowledge that one is so sick. His daughter probably thinks of him as her rescuer and she needs rescuing by moving back close and when this is not historically a healthy relaitonship is only adds to the stress of the cancer. This is the one time when cancer gets to win--family and friends either abide by the reality that he is too sick to care for any of them, or they move on.
I apologize for sounding so harsh, but your husband needs his strength and he needs you to be able to focus on him and not bear the burden of others troubles for him. I hope you can figure out what will work best for you both and keep us posted on how it is going. This board is wonderful and othes, most likely, have a kinder approach than I (It's the social worker in me:).