Hi OP, I haven’t been in this situation myself, but my sister has and she was (and still is) so, so much happier since she left.
She was with a guy for about ten years and at the point she left, there two children were 7 and 4. I was at her house on a Wednesday, she broke down and told me how she and the children were being emotionally and financially abused and she couldn’t go on. I was so, so shocked - she had been hiding it for years.
Anyhow, two days later when her partner was at work I went to their house and bundled my sister and the children into my car, with hardly any belongings and took them back to my house. She text her partner to say she had left and then blocked him. He will have known she was with me but thankfully he didn’t know where I lived.
It was a difficult year after she left when it came to trying to find somewhere else to live, to sort her finances out, readjust to life (both children had to move school) and deal with all the emotional impact it had on the children.
The 5 year old was too young to really understand and seemed to think coming to mine was a big adventure. The 7 year old however was very damaged by what he’d been witnessing at home, especially seeing how his dad was treating his mom, and it was all very upsetting for him although he said from Day one that he was so glad he didn’t have to live with his daddy anymore.
It’s been over 7 years since my sister left her Ex and still her son will not have anything to do with his dad. He says he will never forgive or forget what his dad did.
My sister has such a wonderful life now, she is so happy, the children are thriving, she has so many friends and a wonder social life and that terrible period of her life is just a memory that she doesn’t even pay attention to anymore.
You are a wonderful mother and so incredibly brave - life may be difficult for a while but from the moment you leave it’s the start of your new and happy life with your daughter.
The best of luck to both of you 