Im sorry that you are having to go through this.
There's a lot of unknown going on there. In the end, sadly there is no way to make either of them do anything.
my own biological mom, i had to just cut off contact with her. things seemed horrible and only got worse, and she would come to me to help her. but end the end, no matter what i said or did, she is still with the guy. i have found out over the years that my bio mom likes to "play victim", as she thrives in the attention she gets from it. it doesnt really sound like your mom is like that though. she may be scared of a lot of things(where to sleep, what might change, etc.) . she really needs a therapist...
my goes out to you!

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