Is this weird? What should I do?

My “dad” is extremely toxic so when I moved out with my 11 month old, I decided to only visit with my mom and siblings. We would visit every weekend, since he would work. It’s been this way for months, aside from holidays or another visit or two where we saw him too, and I didn’t think there was an issue. But about a week ago, we met up to visit at her mom’s and she admitted to me almost instantly as soon as we were alone that he would basically punish her for me not living there or wanting to be around him anymore. The only thing she would tell me is that he would act disgusted with her (facial expression, shooing her off) or would tell her she needs to go away. Which I had NO idea because he would act all sweet and cuddly to her when we were around or always talked about how much he loves her, how awesome he is, etc. I would’ve never guessed it was all fake. And the scary part is that I feel like she’s not even telling me the worst of it.

Since then, I can tell that she has distanced. She takes longer to answer and ignores a lot of my messages lately. Or if I try to spend time with her, even if it’s not in the home, like just to join her on errands, she blows me off. Even though I’ve had a medical scare that landed me in the hospital, she seemed super hesitant to come visit me in the hospital.

I’m not sure what to make of this or what to do. I feel like I should be worried but I know there’s not much I can do.