My situation is far worse but actually the same.
My mom loves and defences him but he freaking raped me when my younger brother was looking after his horses he did that to me knowing I can’t stick up for myself.
No one knows about it except me and my mom and one of my uncles!
Damn it!
I want him to die or being shut in the police!
The most creepiest thing that he is an energy vampire as well as my mom!
But my mom is weakest one!
Talk to a counsellor. Decide if you want to go to the police. I think you should report it and then you can decide to press charges. The choice is up to you. The choice is a rock and a hard place but getting help from professionals will make sure you can still live your best life.