How to cope as a new caregiver? I truly can't stand to go home after work.

Your mother is treating you and your family like she's doing the lot of you some kind of favor by having all of you there. She isn't and you need to remind her that the reason why she isn't in a nursing home is because you and your family agreed to live with her.
Remind her that you and your family can go right back to living in your own place with your own things as you like them.
Please, don't ever let it slide when she starts up or even insinuates anything like 'doing you and your family a favor' or 'letting you and your family move in'. Do not tolerate that for one moment.

It's time for you and your family to go back to your own place. Hire a live-in caregiver/companion for your mother who will be paid for out of her funds. Let the caregiver/companion sit with her 24 hours a day.
Families always make an idyllic image of multi-generational living in their minds which is never what it actually is. People think it's going to be like a Hallmark Christmas movie when they move themselves and spouses and kids in with the grandparents, or move the grandparents in with them. It's never like this.
The truth of it is elderly people will double-down on the complaining, instigating, and orneriness because there's a bigger audience to either get attention from or to stir up trouble with. If it's the family moving into the elder's home, well God help them because their lives become an unbearable misery. Multi-generational living does not work today in western cultures.
Go back to your home before your kids and husband start to resent you for making them live how they are now.

The problem is not that she moved in with mom but that they frequently have 7 people there! Her grown kids should be on their own - show them the door. It's no wonder grandma is cantankerous. How about your family takes turns spending the night with grandma? That's the way we did it with my grandma. Can't imagine my mom's family of 9 moving in with her! Grandma needs peace and quiet. (And before the rest of you responders get your knickers in a wad, which of you agrees with her moving 7 people in?) This should be evaluated by APS.

I think it's wonderful that you are trying to help your mom but all of you are in an untenable position. I'm a recently retired nurse and for the first time in over 20 years, I don't have a family member living with me, and I hate to admit this because I loved them but I had forgotten what it was like to have any free time at all. I now have my own medical problems so have to now make that a priority. All of the posts make great points. However, one thing I would do if I were you is consult an elder attorney (or at least your county dept of social services). Many of them will talk with you over the phone for an initial free consultation. One thing they will say is don't spend your money on your mom unless money is not an issue. IF you decide to place mom in a facility, she has to spend her money down until she has very little left (usually about $2,000 depending on the state) before she can become potentially eligible for Medicaid. Any facility that accepts Medicaid cannot discriminate on the basis of payment source. Some will tell you that you have to pay the full price for 3 years, then they will accept Medicaid but this is actually against the law at least in my state. Any decent facility is going to cost a bundle. But home care is not cheap and it's difficult. I had to place one family member with advanced dementia in a facility because he was a very large man and he had broken his hip and leg in a fall from the sofa onto carpet. Even in the best facilities, you have to keep an eye on things. However, the cost to your family and you is also very high. It sounds obvious but you have to figure out a plan and have someone help you. Alot depends on what you WANT to do and CAN do. I will tell you this though..taking care of a dementia patient is way harder than taking care of someone who can cooperate. It's not your mom's fault or yours. You're in a bad situation. But you are going to be dealing with wandering, incontinence, mood swings, and alot of other things that she can't help....and think how she feels that she is in her own home but now it may not feel like it. Also, alot of elderly people with dementia (and even without) have medical problems and, e.g., sometimes they get urinary retention and have to be catheterized or they fall or...something else. Will someone be able to always be with her, be able to be flexible enough to take her to the doctor for planned and unplanned visits? On the other hand, it's only natural to want to be in your own home. It takes tremendous coordination and a united family to care for someone at home. I suggest you try making the living situation as bearable as possible for the near term and get your kids to help with grandma while you and your husband figure out a plan. Sounds like you can do this for a bit longer but not forever. The Alzheimer's association is also a great organization and can help you think through things. I wish you all well. It's the hardest job in the world but remember you can take care of mom yourself OR in a facility. You just have to make the best decision you can. Good luck.

I think it's wonderful that you are trying to help your mom but all of you are in an untenable position. I'm a recently retired nurse and for the first time in over 20 years, I don't have a family member living with me, and I hate to admit this because I loved them but I had forgotten what it was like to have any free time at all. I now have my own medical problems so have to now make that a priority. All of the posts make great points. However, one thing I would do if I were you is consult an elder attorney (or at least your county dept of social services). Many of them will talk with you over the phone for an initial free consultation. One thing they will say is don't spend your money on your mom unless money is not an issue. IF you decide to place mom in a facility, she has to spend her money down until she has very little left (usually about $2,000 depending on the state) before she can become potentially eligible for Medicaid. Any facility that accepts Medicaid cannot discriminate on the basis of payment source. Some will tell you that you have to pay the full price for 3 years, then they will accept Medicaid but this is actually against the law at least in my state. Any decent facility is going to cost a bundle. But home care is not cheap and it's difficult. I had to place one family member with advanced dementia in a facility because he was a very large man and he had broken his hip and leg in a fall from the sofa onto carpet. Even in the best facilities, you have to keep an eye on things. However, the cost to your family and you is also very high. It sounds obvious but you have to figure out a plan and have someone help you. Alot depends on what you WANT to do and CAN do. I will tell you this though..taking care of a dementia patient is way harder than taking care of someone who can cooperate. It's not your mom's fault or yours. You're in a bad situation. But you are going to be dealing with wandering, incontinence, mood swings, and alot of other things that she can't help....and think how she feels that she is in her own home but now it may not feel like it. Also, alot of elderly people with dementia (and even without) have medical problems and, e.g., sometimes they get urinary retention and have to be catheterized or they fall or...something else. Will someone be able to always be with her, be able to be flexible enough to take her to the doctor for planned and unplanned visits? On the other hand, it's only natural to want to be in your own home. It takes tremendous coordination and a united family to care for someone at home. I suggest you try making the living situation as bearable as possible for the near term and get your kids to help with grandma while you and your husband figure out a plan. Sounds like you can do this for a bit longer but not forever. The Alzheimer's association is also a great organization and can help you think through things. I wish you all well. It's the hardest job in the world but remember you can take care of mom yourself OR in a facility. You just have to make the best decision you can. Good luck.