..you're going through this. I kept my.mother for nearly 5 years as her dementia worsened. I finally went the memory care route when her incontinence and paranoid sundowning episodes made it unsafe for her to be at my home. I was utterly exhausted, guilt-ridden, and broken. In retrospect, I honestly wish I had done it sooner because I finally got to be her daughter again, instead of her 24/7 worn-out caregiver.
If your husband is receiving good care and settling in at the memory care, that is a gift. It can never be as good as you, but it can still be the best possible for now.
The one thing about dementia I had to come to terms with is that no matter how well I cared for Mom, I could not turn back time and put her pieces back together. There were simply too many missing. There comes a time that, as a caregiver, you must care for yourself as well, and let others help you.
I am sure your husband would want that for you. My sincere and heartfelt sympathy to you for all you are going through. 
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