My husband decided to have his mom (75) with dementia come live with us without a conversation with me. Now I feel resentful. Is that awful?

No, it's not awful that you feel as you do; it's awful that your husband decided to move his demented mother into your home without a previous discussion with you, therefore, blindsiding you and then leaving her care in YOUR hands. That's not what teamwork in a marriage looks like, and I don't blame you for being unhappy.

Your mother in law *MIL* is also quite young at 75 and can live a lot longer as she continues deteriorating. If it were me, I'd have a Come to Jesus meeting with DH right away to let him know I'm DONE with the hands on caregiving for his mother. He can either hire someone to come into your home to do it, or, he can move her into a Memory Care Assisted Living Facility *ALF* right away. If he refuses, you can move into a hotel for a while while HE takes on the hands-on duties of bathing, changing and cleaning her up 24/7, not to mention cooking and cleaning the house. That may change his attitude mighty fast.

Marriage is a two way street where both people have to communicate properly and respect one another's wishes as well. Moving someone else into the inner sanctum is a big no-no unless everyone, including the children, are on board and willing to help out with the burden. That wasn't the case with your MIL moving in, so now is the time to make some changes.

Wishing you the best of luck moving forward.

It was my husband's decision to move MY mother in with us. Within 6 weeks, I was bedridden with the stress.

I went away for a week, and he was left with her. She was moved out of here quickly after that.

NO WAY are you in the wrong. Absolutely no way.

Oh. Hell. No. What he did for his mom may make him a sterling son, but not asking his partner for an opinion in a life altering change makes him a tarnished husband.

It is understandable how you feel.
I would not feel resentful if my husband had done the same I would be royally pissed off!!!
I think that you should put a halt to some of "your" caregiving duties and let him take over for a while.
It might go something like this...
Come Friday book a weekend in a local hotel, one with a pool, hot tub and when hubby comes home Friday night you and your daughter take off for a mom and daughter weekend. (you might want to forget the charger to your phone.) Come home Sunday all rested and then have a sit down talk with hubby and say.."you did this for a weekend, I do it all week, for almost 4 years now. We need to find Memory Care for mom"

Boundaries:
“The only people who get upset when you set boundaries, are the ones who benefited from you having none.”
Plan a vacation with your child and tell your husband to “hire a caregiver,” and send him a postcard.
Its always dumped on one human.

You can move out, with your child, without a conversation with him too.

This issue is a big one & often does need a marriage counselor.

I remember a past poster who was threatened with divorce if she did not care for his Mom 12hrs/day & continue her job too.

I penned an ad for him "Man, middle aged, seeks wife #2 to care for MIL all day & work nights to pay for household expences. Also to do all household chores".

Wonder how that turned out?

You feel like your child and yourself are suffering because you are. Your husband needs to step up and start thinking of the welfare of his wife and daughter.
You did not agree to become your MIL's caregiver. One of the members of this forum came up with the word that perfectly describes what has happened in your situation.

You were 'VOLUNTOLD' and it was assumed that you'd become your MIL's caregiver. No one has the right to assume and put the responsibility and care of their needy elder on someone else for any reason. You DO NOT have to take care of your MIL, and it's high time you threw down the gauntlet with your husband about it. That MIL goes or you and your daughter do.
I mean no disrespect to your husband or family, but he created this situation and sustains it so he can have his cake and eat it too. He can be the hero and the good son who takes his poor, needy mother into his house and everyone applauds him. Only his wife is the one who has to take on all the responsibility for her and meet all of her care needs. Nope. That sh*t has to stop today.
You tell your old man in plain English that you will not care for his mother anymore.

It saddens me that your husband disrespected your marriage to such an extent that he would do this without consulting you. That says a lot about your marriage, and even when Mom's out of the house, you two need some counseling about how to communicate and work as a team.

Now that I'm done being Dear Abby, the reality is that Mom could last another 10 years. Seventy-five isn't all that old, so I completely agree with the suggestion that you bail out for a long weekend, then come home and have the "come to Jesus" moment with your husband. This situation is untenable -- period -- and it does no service to his mother for her to have less than the best care.

Not that you aren't providing excellent care, but a memory care with staff who can handle her needs 24 hours a day is far superior to one person doing all the work that will not lessen as time goes on. The reality is that the day is coming when she needs more care than you can provide, so now is the time to take the bull by the horns and get her set up in a memory care facility before it reaches crisis level. Once that's done, tackle your marriage.

I know that some of the suggestions about checking into a hotel for the weekend, going on a week’s holiday etc, just aren’t financially feasible for many people. What is possible is just to stop doing the jobs you have been ‘volunteered’ for. I think it would be polite, and possibly productive, to discuss this with MIL and tell her what and why you are stopping the jobs.

She will be fine without regular showers – lots of posters have parents who haven’t washed for months and have still managed to avoid skin problems.
You can have frozen meals in the fridge and she or DH can heat them up.
The Depends cleanup can wait for DH to get home, at least for a few days.
She can stay in bed – you don’t have to get her up.

You don’t have to be nasty about this. Let MIL deal with any anger with DH, not you.

If you keep on doing all the jobs, neither DH, MIL or the various relations have any incentive to change. You need to stop doing them, and let the chips fall where they may.

If your husband wants to keep Mommy at home, then he will need to quit his job and take care of her. This isn’t your job.