Wondering how can I "take time" for myself when there's no one else to watch mom?

Figure out what you would do if you didn't have siblings, because for all practical purposes you don't.

I think the place to start is to find out what your mother is eligible for. Many seniors can't afford to pay their own way for the rest of their lives. Call your county's agency for senior services, explain the situation, and ask for an appointment with a social worker. That professional will know what programs and resources are available in your area. That might include senior day centers, waiver programs designed to help keep the elderly in the community, and it will include applying for Medicaid. Get started on this as soon as you can ... tomorrow would be good. If she isn't quite qualified for Medicaid you will know why and what to do about it. If she can't afford a nursing home, Medicaid will cover that when the time comes.

This is also the time to take care of all the legal technicalities, if you haven't already. Take of POA, Medical Proxy, and Healthcare Directives. Since you are living in her house (did I get that right?) it would be good to set up a contract spelling out the care you are providing and what you are getting in return. See an attorney specializing in elder law. Yes, it is one more expense, but it is essential and will be well worth it, especially in light of the conflicts that exist in the family.

Now, about taking time for yourselves. You HAVE to do it. Speaking from experience it can be very hard to arrange, but it is necessary. Does Mom have a pension or SS check? Some of that money should go toward paying for respite care. The social worker you are going to set up an appointment with tomorrow (right?) should be able to help you find out how to locate in-home respite care and also respite care in a facility, where your mom would spend a week while you are on vacation.

You need help figuring out what is available. There will be no cost getting professional help. Do it!

You need to get things on a good legal footing. That will cost something, but it will be worth it. Do that, too!

Best of luck to you as you struggle along the path.

Does your mother qualify for medicaide? There are home health care organizations in some places. It sounds like you and your husband are at a breaking point with your mother. Does your mother need you to be right there or guilt you into believing she needs you right there all of the time?