AITA for breaking my deathbed promise to my wife to take care of her Down's Syndrome daughter?

I ( 55M) just lost my wife (56F) to cancer.

My late wife's entire life was about her 30 year old daughter, who suffers from Down's Syndrome and has never and will never have the ability to live independently. Nor will she ever have the ability to ever exercise any real amount of emotional impulse control.

And before you all start in on the " evil stepdad who doesn't care to understand" line of thinking, I want to add that I have been in her life since she was 5. And spent years fearing the day where she was physically developed to the point where punches, scratches, and throwing things were a real threat. Once that happened, all of my wife's friends stopped visiting our house. One of them even said that her uncle deals with vicious dogs for a living and she feels safer around his workplace than at our house.

I many times have ended up needing to go to the doctor's for the crime of sitting in the same room as my stepdaughter and having her attempt to pound my head in, throw a heavy object at me, or trying to choke me after I had fallen asleep.

My late wife was the only one who could reliably calm her down. When we started using caregivers for my stepdaughter after my wife was diagnosed, THEY would be asking ME whether I could enlighten them on a better way to explain things to my stepdaughter when she was going ballistic. When even they, who were used to explaining things to people who just didn't get things were still struggling and asking for insight.

When my late wife was diagnosed, the first word out of her mouth was my stepdaughter's name. She cried every day for what was to become of her. In her desperation, she tried to press the doctor for chemotherapy when it no longer made sense. Turned to alternative medicine despite it making her feel worse. Saying she would have stopped all treatment if she was only leaving behind a employable, functioning 30 year old.

On her deathbed, she made me promise to not let her fall into the hands of a state care facility. I promised her because I didn't have the heart not to.

But now after my grief fog has cleared 2 months later my stepdaughter remains the same. She doesn't understand her mom is dead- only that she's gone and is angry at me for it. Saying she'll be good, so bring her back.

Caregivers are expensive. I don't make much. I didn't resent any medical expenses when it was my wife but I admit that I resent my stepdaughter. My own grown kids won't visit with her around. If I hadn't made the death bed promise the decision would have been easy.

And finally I made the decision that I needed to put her in a state run facility, as even with my wife leaving me everything, I couldn't afford anything " better." Now family are calling me the evil stepdad and a mother's worst nightmare. AITA?

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