Sorry op but I think it's a case of you THINK it's hard to leave
It's really not.
You're afraid of the unknown. Common enough. But the unknown I guarantee you will be better than how things are now.
I promise you it may be hard in the initial stages but in a year or so of leaving you will wonder why you didn't do it earlier.
My mother remained married to my very abusive father. That decision fucked up my siblings and I for life. Not just because of the abuse but because we didn't have a mother we could rely on to protect
BELIEVE ME you don't want to be her.
She very much regrets staying and my brother and I as a result barely have a relationship with her. My sister only does in order to use her for childcare and money.
My dd barely knows her gran as I made the decision in order to protect her to not allow her to have unsupervised contact with either of my parents ever. My brother moved over 400 miles away and his kids barely know her.
Is that what you want? Do you want to have wasted your life? Your motherhood on an abusive, selfish and destructive man?
Do you want your dc to have Mh problems for the rest of their lives?
I'm 49 I will NEVER recover from the results of her decision not to leave.
I love her I recognise she was also a victim. But I cannot forgive her for not leaving, she had ample opportunity and resources to do so and even if she hadn't even if it had been a case of going to a refuge initially and having no money (which we didn't have anyway as he drank it away) we'd have been better off than we were with her staying.
What would your dc want you to do?